diff --git a/OpenTween.Tests/Api/GraphQL/CreateRetweetRequestTest.cs b/OpenTween.Tests/Api/GraphQL/CreateRetweetRequestTest.cs
index 418d38f7f..5fee38558 100644
--- a/OpenTween.Tests/Api/GraphQL/CreateRetweetRequestTest.cs
+++ b/OpenTween.Tests/Api/GraphQL/CreateRetweetRequestTest.cs
@@ -38,7 +38,7 @@ public async Task Send_Test()
         {
             var responseText = File.ReadAllText("Resources/Responses/CreateRetweet.json");
 
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                     x.PostJsonAsync(It.IsAny<Uri>(), It.IsAny<string>())
                 )
diff --git a/OpenTween.Tests/Api/GraphQL/CreateTweetRequestTest.cs b/OpenTween.Tests/Api/GraphQL/CreateTweetRequestTest.cs
index ef5d8e85d..ad08aec06 100644
--- a/OpenTween.Tests/Api/GraphQL/CreateTweetRequestTest.cs
+++ b/OpenTween.Tests/Api/GraphQL/CreateTweetRequestTest.cs
@@ -38,7 +38,7 @@ public async Task Send_Test()
         {
             var responseText = File.ReadAllText("Resources/Responses/CreateTweet_CircleTweet.json");
 
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                     x.PostJsonAsync(It.IsAny<Uri>(), It.IsAny<string>())
                 )
@@ -67,7 +67,7 @@ public async Task Send_ReplyTest()
         {
             var responseText = File.ReadAllText("Resources/Responses/CreateTweet_CircleTweet.json");
 
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                     x.PostJsonAsync(It.IsAny<Uri>(), It.IsAny<string>())
                 )
@@ -92,7 +92,7 @@ public async Task Send_MediaTest()
         {
             var responseText = File.ReadAllText("Resources/Responses/CreateTweet_CircleTweet.json");
 
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                     x.PostJsonAsync(It.IsAny<Uri>(), It.IsAny<string>())
                 )
diff --git a/OpenTween.Tests/Api/GraphQL/DeleteRetweetRequestTest.cs b/OpenTween.Tests/Api/GraphQL/DeleteRetweetRequestTest.cs
index fad2f630c..9a52489d3 100644
--- a/OpenTween.Tests/Api/GraphQL/DeleteRetweetRequestTest.cs
+++ b/OpenTween.Tests/Api/GraphQL/DeleteRetweetRequestTest.cs
@@ -36,7 +36,7 @@ public class DeleteRetweetRequestTest
         [Fact]
         public async Task Send_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                     x.PostJsonAsync(It.IsAny<Uri>(), It.IsAny<string>())
                 )
diff --git a/OpenTween.Tests/Api/GraphQL/DeleteTweetRequestTest.cs b/OpenTween.Tests/Api/GraphQL/DeleteTweetRequestTest.cs
index f8c1583e7..3db62ccec 100644
--- a/OpenTween.Tests/Api/GraphQL/DeleteTweetRequestTest.cs
+++ b/OpenTween.Tests/Api/GraphQL/DeleteTweetRequestTest.cs
@@ -36,7 +36,7 @@ public class DeleteTweetRequestTest
         [Fact]
         public async Task Send_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                     x.PostJsonAsync(It.IsAny<Uri>(), It.IsAny<string>())
                 )
diff --git a/OpenTween.Tests/Api/GraphQL/ListLatestTweetsTimelineRequestTest.cs b/OpenTween.Tests/Api/GraphQL/ListLatestTweetsTimelineRequestTest.cs
index cf623b50c..4cb9c952d 100644
--- a/OpenTween.Tests/Api/GraphQL/ListLatestTweetsTimelineRequestTest.cs
+++ b/OpenTween.Tests/Api/GraphQL/ListLatestTweetsTimelineRequestTest.cs
@@ -19,14 +19,8 @@
 // the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
 // Boston, MA 02110-1301, USA.
 
-using System;
-using System.Collections.Generic;
-using System.IO;
-using System.Linq;
-using System.Text;
 using System.Threading.Tasks;
 using Moq;
-using OpenTween.Api.TwitterV2;
 using OpenTween.Connection;
 using Xunit;
 
@@ -37,21 +31,23 @@ public class ListLatestTweetsTimelineRequestTest
         [Fact]
         public async Task Send_Test()
         {
-            using var responseStream = File.OpenRead("Resources/Responses/ListLatestTweetsTimeline_SimpleTweet.json");
+            using var apiResponse = await TestUtils.CreateApiResponse("Resources/Responses/ListLatestTweetsTimeline_SimpleTweet.json");
 
             var mock = new Mock<IApiConnection>();
             mock.Setup(x =>
-                    x.GetStreamAsync(It.IsAny<Uri>(), It.IsAny<IDictionary<string, string>>(), It.IsAny<string>())
+                    x.SendAsync(It.IsAny<IHttpRequest>())
                 )
-                .Callback<Uri, IDictionary<string, string>, string>((url, param, endpointName) =>
+                .Callback<IHttpRequest>(x =>
                 {
-                    Assert.Equal(new("https://twitter.com/i/api/graphql/6ClPnsuzQJ1p7-g32GQw9Q/ListLatestTweetsTimeline"), url);
-                    Assert.Equal(2, param.Count);
-                    Assert.Equal("""{"listId":"1675863884757110790","count":20}""", param["variables"]);
-                    Assert.True(param.ContainsKey("features"));
-                    Assert.Equal("ListLatestTweetsTimeline", endpointName);
+                    var request = Assert.IsType<GetRequest>(x);
+                    Assert.Equal(new("https://twitter.com/i/api/graphql/6ClPnsuzQJ1p7-g32GQw9Q/ListLatestTweetsTimeline"), request.RequestUri);
+                    var query = request.Query!;
+                    Assert.Equal(2, query.Count);
+                    Assert.Equal("""{"listId":"1675863884757110790","count":20}""", query["variables"]);
+                    Assert.True(query.ContainsKey("features"));
+                    Assert.Equal("ListLatestTweetsTimeline", request.EndpointName);
                 })
-                .ReturnsAsync(responseStream);
+                .ReturnsAsync(apiResponse);
 
             var request = new ListLatestTweetsTimelineRequest(listId: "1675863884757110790")
             {
@@ -69,21 +65,23 @@ public async Task Send_Test()
         [Fact]
         public async Task Send_RequestCursor_Test()
         {
-            using var responseStream = File.OpenRead("Resources/Responses/ListLatestTweetsTimeline_SimpleTweet.json");
+            using var apiResponse = await TestUtils.CreateApiResponse("Resources/Responses/ListLatestTweetsTimeline_SimpleTweet.json");
 
             var mock = new Mock<IApiConnection>();
             mock.Setup(x =>
-                    x.GetStreamAsync(It.IsAny<Uri>(), It.IsAny<IDictionary<string, string>>(), It.IsAny<string>())
+                    x.SendAsync(It.IsAny<IHttpRequest>())
                 )
-                .Callback<Uri, IDictionary<string, string>, string>((url, param, endpointName) =>
+                .Callback<IHttpRequest>(x =>
                 {
-                    Assert.Equal(new("https://twitter.com/i/api/graphql/6ClPnsuzQJ1p7-g32GQw9Q/ListLatestTweetsTimeline"), url);
-                    Assert.Equal(2, param.Count);
-                    Assert.Equal("""{"listId":"1675863884757110790","count":20,"cursor":"aaa"}""", param["variables"]);
-                    Assert.True(param.ContainsKey("features"));
-                    Assert.Equal("ListLatestTweetsTimeline", endpointName);
+                    var request = Assert.IsType<GetRequest>(x);
+                    Assert.Equal(new("https://twitter.com/i/api/graphql/6ClPnsuzQJ1p7-g32GQw9Q/ListLatestTweetsTimeline"), request.RequestUri);
+                    var query = request.Query!;
+                    Assert.Equal(2, query.Count);
+                    Assert.Equal("""{"listId":"1675863884757110790","count":20,"cursor":"aaa"}""", query["variables"]);
+                    Assert.True(query.ContainsKey("features"));
+                    Assert.Equal("ListLatestTweetsTimeline", request.EndpointName);
                 })
-                .ReturnsAsync(responseStream);
+                .ReturnsAsync(apiResponse);
 
             var request = new ListLatestTweetsTimelineRequest(listId: "1675863884757110790")
             {
diff --git a/OpenTween.Tests/Api/GraphQL/SearchTimelineRequestTest.cs b/OpenTween.Tests/Api/GraphQL/SearchTimelineRequestTest.cs
index f424861d8..7003b27c3 100644
--- a/OpenTween.Tests/Api/GraphQL/SearchTimelineRequestTest.cs
+++ b/OpenTween.Tests/Api/GraphQL/SearchTimelineRequestTest.cs
@@ -19,11 +19,6 @@
 // the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
 // Boston, MA 02110-1301, USA.
 
-using System;
-using System.Collections.Generic;
-using System.IO;
-using System.Linq;
-using System.Text;
 using System.Threading.Tasks;
 using Moq;
 using OpenTween.Connection;
@@ -36,21 +31,23 @@ public class SearchTimelineRequestTest
         [Fact]
         public async Task Send_Test()
         {
-            using var responseStream = File.OpenRead("Resources/Responses/SearchTimeline_SimpleTweet.json");
+            using var apiResponse = await TestUtils.CreateApiResponse("Resources/Responses/SearchTimeline_SimpleTweet.json");
 
             var mock = new Mock<IApiConnection>();
             mock.Setup(x =>
-                    x.GetStreamAsync(It.IsAny<Uri>(), It.IsAny<IDictionary<string, string>>(), It.IsAny<string>())
+                    x.SendAsync(It.IsAny<IHttpRequest>())
                 )
-                .Callback<Uri, IDictionary<string, string>, string>((url, param, endpointName) =>
+                .Callback<IHttpRequest>(x =>
                 {
-                    Assert.Equal(new("https://twitter.com/i/api/graphql/lZ0GCEojmtQfiUQa5oJSEw/SearchTimeline"), url);
-                    Assert.Equal(2, param.Count);
-                    Assert.Equal("""{"rawQuery":"#OpenTween","count":20,"product":"Latest"}""", param["variables"]);
-                    Assert.True(param.ContainsKey("features"));
-                    Assert.Equal("SearchTimeline", endpointName);
+                    var request = Assert.IsType<GetRequest>(x);
+                    Assert.Equal(new("https://twitter.com/i/api/graphql/lZ0GCEojmtQfiUQa5oJSEw/SearchTimeline"), request.RequestUri);
+                    var query = request.Query!;
+                    Assert.Equal(2, query.Count);
+                    Assert.Equal("""{"rawQuery":"#OpenTween","count":20,"product":"Latest"}""", query["variables"]);
+                    Assert.True(query.ContainsKey("features"));
+                    Assert.Equal("SearchTimeline", request.EndpointName);
                 })
-                .ReturnsAsync(responseStream);
+                .ReturnsAsync(apiResponse);
 
             var request = new SearchTimelineRequest(rawQuery: "#OpenTween")
             {
@@ -68,21 +65,23 @@ public async Task Send_Test()
         [Fact]
         public async Task Send_RequestCursor_Test()
         {
-            using var responseStream = File.OpenRead("Resources/Responses/SearchTimeline_SimpleTweet.json");
+            using var apiResponse = await TestUtils.CreateApiResponse("Resources/Responses/SearchTimeline_SimpleTweet.json");
 
             var mock = new Mock<IApiConnection>();
             mock.Setup(x =>
-                    x.GetStreamAsync(It.IsAny<Uri>(), It.IsAny<IDictionary<string, string>>(), It.IsAny<string>())
+                    x.SendAsync(It.IsAny<IHttpRequest>())
                 )
-                .Callback<Uri, IDictionary<string, string>, string>((url, param, endpointName) =>
+                .Callback<IHttpRequest>(x =>
                 {
-                    Assert.Equal(new("https://twitter.com/i/api/graphql/lZ0GCEojmtQfiUQa5oJSEw/SearchTimeline"), url);
-                    Assert.Equal(2, param.Count);
-                    Assert.Equal("""{"rawQuery":"#OpenTween","count":20,"product":"Latest","cursor":"aaa"}""", param["variables"]);
-                    Assert.True(param.ContainsKey("features"));
-                    Assert.Equal("SearchTimeline", endpointName);
+                    var request = Assert.IsType<GetRequest>(x);
+                    Assert.Equal(new("https://twitter.com/i/api/graphql/lZ0GCEojmtQfiUQa5oJSEw/SearchTimeline"), request.RequestUri);
+                    var query = request.Query!;
+                    Assert.Equal(2, query.Count);
+                    Assert.Equal("""{"rawQuery":"#OpenTween","count":20,"product":"Latest","cursor":"aaa"}""", query["variables"]);
+                    Assert.True(query.ContainsKey("features"));
+                    Assert.Equal("SearchTimeline", request.EndpointName);
                 })
-                .ReturnsAsync(responseStream);
+                .ReturnsAsync(apiResponse);
 
             var request = new SearchTimelineRequest(rawQuery: "#OpenTween")
             {
diff --git a/OpenTween.Tests/Api/GraphQL/TweetDetailRequestTest.cs b/OpenTween.Tests/Api/GraphQL/TweetDetailRequestTest.cs
index 93e857f20..e88f82311 100644
--- a/OpenTween.Tests/Api/GraphQL/TweetDetailRequestTest.cs
+++ b/OpenTween.Tests/Api/GraphQL/TweetDetailRequestTest.cs
@@ -19,14 +19,9 @@
 // the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
 // Boston, MA 02110-1301, USA.
 
-using System;
-using System.Collections.Generic;
-using System.IO;
 using System.Linq;
-using System.Text;
 using System.Threading.Tasks;
 using Moq;
-using OpenTween.Api.TwitterV2;
 using OpenTween.Connection;
 using Xunit;
 
@@ -37,19 +32,21 @@ public class TweetDetailRequestTest
         [Fact]
         public async Task Send_Test()
         {
-            using var responseStream = File.OpenRead("Resources/Responses/TweetDetail.json");
+            using var apiResponse = await TestUtils.CreateApiResponse("Resources/Responses/TweetDetail.json");
 
             var mock = new Mock<IApiConnection>();
             mock.Setup(x =>
-                    x.GetStreamAsync(It.IsAny<Uri>(), It.IsAny<IDictionary<string, string>>(), It.IsAny<string>())
+                    x.SendAsync(It.IsAny<IHttpRequest>())
                 )
-                .Callback<Uri, IDictionary<string, string>, string>((url, param, endpointName) =>
+                .Callback<IHttpRequest>(x =>
                 {
-                    Assert.Equal(new("https://twitter.com/i/api/graphql/-Ls3CrSQNo2fRKH6i6Na1A/TweetDetail"), url);
-                    Assert.Contains(@"""focalTweetId"":""1619433164757413894""", param["variables"]);
-                    Assert.Equal("TweetDetail", endpointName);
+                    var request = Assert.IsType<GetRequest>(x);
+                    Assert.Equal(new("https://twitter.com/i/api/graphql/-Ls3CrSQNo2fRKH6i6Na1A/TweetDetail"), request.RequestUri);
+                    var query = request.Query!;
+                    Assert.Contains(@"""focalTweetId"":""1619433164757413894""", query["variables"]);
+                    Assert.Equal("TweetDetail", request.EndpointName);
                 })
-                .ReturnsAsync(responseStream);
+                .ReturnsAsync(apiResponse);
 
             var request = new TweetDetailRequest
             {
diff --git a/OpenTween.Tests/Api/GraphQL/UserByScreenNameRequestTest.cs b/OpenTween.Tests/Api/GraphQL/UserByScreenNameRequestTest.cs
index 075ee3462..9c4e287d9 100644
--- a/OpenTween.Tests/Api/GraphQL/UserByScreenNameRequestTest.cs
+++ b/OpenTween.Tests/Api/GraphQL/UserByScreenNameRequestTest.cs
@@ -19,11 +19,6 @@
 // the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
 // Boston, MA 02110-1301, USA.
 
-using System;
-using System.Collections.Generic;
-using System.IO;
-using System.Linq;
-using System.Text;
 using System.Threading.Tasks;
 using Moq;
 using OpenTween.Connection;
@@ -36,19 +31,21 @@ public class UserByScreenNameRequestTest
         [Fact]
         public async Task Send_Test()
         {
-            using var responseStream = File.OpenRead("Resources/Responses/UserByScreenName.json");
+            using var apiResponse = await TestUtils.CreateApiResponse("Resources/Responses/UserByScreenName.json");
 
             var mock = new Mock<IApiConnection>();
             mock.Setup(x =>
-                    x.GetStreamAsync(It.IsAny<Uri>(), It.IsAny<IDictionary<string, string>>(), It.IsAny<string>())
+                    x.SendAsync(It.IsAny<IHttpRequest>())
                 )
-                .Callback<Uri, IDictionary<string, string>, string>((url, param, endpointName) =>
+                .Callback<IHttpRequest>(x =>
                 {
-                    Assert.Equal(new("https://twitter.com/i/api/graphql/xc8f1g7BYqr6VTzTbvNlGw/UserByScreenName"), url);
-                    Assert.Contains(@"""screen_name"":""opentween""", param["variables"]);
-                    Assert.Equal("UserByScreenName", endpointName);
+                    var request = Assert.IsType<GetRequest>(x);
+                    Assert.Equal(new("https://twitter.com/i/api/graphql/xc8f1g7BYqr6VTzTbvNlGw/UserByScreenName"), request.RequestUri);
+                    var query = request.Query!;
+                    Assert.Contains(@"""screen_name"":""opentween""", query["variables"]);
+                    Assert.Equal("UserByScreenName", request.EndpointName);
                 })
-                .ReturnsAsync(responseStream);
+                .ReturnsAsync(apiResponse);
 
             var request = new UserByScreenNameRequest
             {
@@ -64,13 +61,13 @@ public async Task Send_Test()
         [Fact]
         public async Task Send_UserUnavailableTest()
         {
-            using var responseStream = File.OpenRead("Resources/Responses/UserByScreenName_Suspended.json");
+            using var apiResponse = await TestUtils.CreateApiResponse("Resources/Responses/UserByScreenName_Suspended.json");
 
             var mock = new Mock<IApiConnection>();
             mock.Setup(x =>
-                    x.GetStreamAsync(It.IsAny<Uri>(), It.IsAny<IDictionary<string, string>>(), It.IsAny<string>())
+                    x.SendAsync(It.IsAny<IHttpRequest>())
                 )
-                .ReturnsAsync(responseStream);
+                .ReturnsAsync(apiResponse);
 
             var request = new UserByScreenNameRequest
             {
diff --git a/OpenTween.Tests/Api/GraphQL/UserTweetsAndRepliesRequestTest.cs b/OpenTween.Tests/Api/GraphQL/UserTweetsAndRepliesRequestTest.cs
index b829b193f..50264c609 100644
--- a/OpenTween.Tests/Api/GraphQL/UserTweetsAndRepliesRequestTest.cs
+++ b/OpenTween.Tests/Api/GraphQL/UserTweetsAndRepliesRequestTest.cs
@@ -19,11 +19,6 @@
 // the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
 // Boston, MA 02110-1301, USA.
 
-using System;
-using System.Collections.Generic;
-using System.IO;
-using System.Linq;
-using System.Text;
 using System.Threading.Tasks;
 using Moq;
 using OpenTween.Connection;
@@ -36,21 +31,23 @@ public class UserTweetsAndRepliesRequestTest
         [Fact]
         public async Task Send_Test()
         {
-            using var responseStream = File.OpenRead("Resources/Responses/UserTweetsAndReplies_SimpleTweet.json");
+            using var apiResponse = await TestUtils.CreateApiResponse("Resources/Responses/UserTweetsAndReplies_SimpleTweet.json");
 
             var mock = new Mock<IApiConnection>();
             mock.Setup(x =>
-                    x.GetStreamAsync(It.IsAny<Uri>(), It.IsAny<IDictionary<string, string>>(), It.IsAny<string>())
+                    x.SendAsync(It.IsAny<IHttpRequest>())
                 )
-                .Callback<Uri, IDictionary<string, string>, string>((url, param, endpointName) =>
+                .Callback<IHttpRequest>(x =>
                 {
-                    Assert.Equal(new("https://twitter.com/i/api/graphql/YlkSUg0mRBx7-EkxCvc-bw/UserTweetsAndReplies"), url);
-                    Assert.Equal(2, param.Count);
-                    Assert.Equal("""{"userId":"40480664","count":20,"includePromotedContent":true,"withCommunity":true,"withVoice":true,"withV2Timeline":true}""", param["variables"]);
-                    Assert.True(param.ContainsKey("features"));
-                    Assert.Equal("UserTweetsAndReplies", endpointName);
+                    var request = Assert.IsType<GetRequest>(x);
+                    Assert.Equal(new("https://twitter.com/i/api/graphql/YlkSUg0mRBx7-EkxCvc-bw/UserTweetsAndReplies"), request.RequestUri);
+                    var query = request.Query!;
+                    Assert.Equal(2, query.Count);
+                    Assert.Equal("""{"userId":"40480664","count":20,"includePromotedContent":true,"withCommunity":true,"withVoice":true,"withV2Timeline":true}""", query["variables"]);
+                    Assert.True(query.ContainsKey("features"));
+                    Assert.Equal("UserTweetsAndReplies", request.EndpointName);
                 })
-                .ReturnsAsync(responseStream);
+                .ReturnsAsync(apiResponse);
 
             var request = new UserTweetsAndRepliesRequest(userId: "40480664")
             {
@@ -68,21 +65,23 @@ public async Task Send_Test()
         [Fact]
         public async Task Send_RequestCursor_Test()
         {
-            using var responseStream = File.OpenRead("Resources/Responses/UserTweetsAndReplies_SimpleTweet.json");
+            using var apiResponse = await TestUtils.CreateApiResponse("Resources/Responses/UserTweetsAndReplies_SimpleTweet.json");
 
             var mock = new Mock<IApiConnection>();
             mock.Setup(x =>
-                    x.GetStreamAsync(It.IsAny<Uri>(), It.IsAny<IDictionary<string, string>>(), It.IsAny<string>())
+                    x.SendAsync(It.IsAny<IHttpRequest>())
                 )
-                .Callback<Uri, IDictionary<string, string>, string>((url, param, endpointName) =>
+                .Callback<IHttpRequest>(x =>
                 {
-                    Assert.Equal(new("https://twitter.com/i/api/graphql/YlkSUg0mRBx7-EkxCvc-bw/UserTweetsAndReplies"), url);
-                    Assert.Equal(2, param.Count);
-                    Assert.Equal("""{"userId":"40480664","count":20,"includePromotedContent":true,"withCommunity":true,"withVoice":true,"withV2Timeline":true,"cursor":"aaa"}""", param["variables"]);
-                    Assert.True(param.ContainsKey("features"));
-                    Assert.Equal("UserTweetsAndReplies", endpointName);
+                    var request = Assert.IsType<GetRequest>(x);
+                    Assert.Equal(new("https://twitter.com/i/api/graphql/YlkSUg0mRBx7-EkxCvc-bw/UserTweetsAndReplies"), request.RequestUri);
+                    var query = request.Query!;
+                    Assert.Equal(2, query.Count);
+                    Assert.Equal("""{"userId":"40480664","count":20,"includePromotedContent":true,"withCommunity":true,"withVoice":true,"withV2Timeline":true,"cursor":"aaa"}""", query["variables"]);
+                    Assert.True(query.ContainsKey("features"));
+                    Assert.Equal("UserTweetsAndReplies", request.EndpointName);
                 })
-                .ReturnsAsync(responseStream);
+                .ReturnsAsync(apiResponse);
 
             var request = new UserTweetsAndRepliesRequest(userId: "40480664")
             {
diff --git a/OpenTween.Tests/Api/TwitterApiTest.cs b/OpenTween.Tests/Api/TwitterApiTest.cs
index 49ca6b9ff..d74088b2f 100644
--- a/OpenTween.Tests/Api/TwitterApiTest.cs
+++ b/OpenTween.Tests/Api/TwitterApiTest.cs
@@ -84,7 +84,7 @@ public void Initialize_Test()
         [Fact]
         public async Task StatusesHomeTimeline_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.GetAsync<TwitterStatus[]>(
                     new Uri("statuses/home_timeline.json", UriKind.Relative),
@@ -112,7 +112,7 @@ public async Task StatusesHomeTimeline_Test()
         [Fact]
         public async Task StatusesMentionsTimeline_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.GetAsync<TwitterStatus[]>(
                     new Uri("statuses/mentions_timeline.json", UriKind.Relative),
@@ -140,7 +140,7 @@ public async Task StatusesMentionsTimeline_Test()
         [Fact]
         public async Task StatusesUserTimeline_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.GetAsync<TwitterStatus[]>(
                     new Uri("statuses/user_timeline.json", UriKind.Relative),
@@ -170,7 +170,7 @@ public async Task StatusesUserTimeline_Test()
         [Fact]
         public async Task StatusesShow_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.GetAsync<TwitterStatus>(
                     new Uri("statuses/show.json", UriKind.Relative),
@@ -196,7 +196,7 @@ public async Task StatusesShow_Test()
         [Fact]
         public async Task StatusesLookup_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.GetAsync<TwitterStatus[]>(
                     new Uri("statuses/lookup.json", UriKind.Relative),
@@ -223,7 +223,7 @@ public async Task StatusesLookup_Test()
         [Fact]
         public async Task StatusesUpdate_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.PostLazyAsync<TwitterStatus>(
                     new Uri("statuses/update.json", UriKind.Relative),
@@ -261,7 +261,7 @@ await twitterApi.StatusesUpdate(
         [Fact]
         public async Task StatusesUpdate_ExcludeReplyUserIdsEmptyTest()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.PostLazyAsync<TwitterStatus>(
                     new Uri("statuses/update.json", UriKind.Relative),
@@ -288,7 +288,7 @@ await twitterApi.StatusesUpdate("hogehoge", replyToId: null, mediaIds: null, exc
         [Fact]
         public async Task StatusesDestroy_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.PostLazyAsync<TwitterStatus>(
                     new Uri("statuses/destroy.json", UriKind.Relative),
@@ -308,7 +308,7 @@ public async Task StatusesDestroy_Test()
         [Fact]
         public async Task StatusesRetweet_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.PostLazyAsync<TwitterStatus>(
                     new Uri("statuses/retweet.json", UriKind.Relative),
@@ -334,7 +334,7 @@ await twitterApi.StatusesRetweet(new("100"))
         [Fact]
         public async Task SearchTweets_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.GetAsync<TwitterSearchResult>(
                     new Uri("search/tweets.json", UriKind.Relative),
@@ -365,7 +365,7 @@ public async Task SearchTweets_Test()
         [Fact]
         public async Task ListsOwnerships_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.GetAsync<TwitterLists>(
                     new Uri("lists/ownerships.json", UriKind.Relative),
@@ -390,7 +390,7 @@ public async Task ListsOwnerships_Test()
         [Fact]
         public async Task ListsSubscriptions_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.GetAsync<TwitterLists>(
                     new Uri("lists/subscriptions.json", UriKind.Relative),
@@ -415,7 +415,7 @@ public async Task ListsSubscriptions_Test()
         [Fact]
         public async Task ListsMemberships_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.GetAsync<TwitterLists>(
                     new Uri("lists/memberships.json", UriKind.Relative),
@@ -441,7 +441,7 @@ public async Task ListsMemberships_Test()
         [Fact]
         public async Task ListsCreate_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.PostLazyAsync<TwitterList>(
                     new Uri("lists/create.json", UriKind.Relative),
@@ -466,7 +466,7 @@ await twitterApi.ListsCreate("hogehoge", description: "aaaa", @private: true)
         [Fact]
         public async Task ListsUpdate_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.PostLazyAsync<TwitterList>(
                     new Uri("lists/update.json", UriKind.Relative),
@@ -492,7 +492,7 @@ await twitterApi.ListsUpdate(12345L, name: "hogehoge", description: "aaaa", @pri
         [Fact]
         public async Task ListsDestroy_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.PostLazyAsync<TwitterList>(
                     new Uri("lists/destroy.json", UriKind.Relative),
@@ -515,7 +515,7 @@ await twitterApi.ListsDestroy(12345L)
         [Fact]
         public async Task ListsStatuses_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.GetAsync<TwitterStatus[]>(
                     new Uri("lists/statuses.json", UriKind.Relative),
@@ -545,7 +545,7 @@ public async Task ListsStatuses_Test()
         [Fact]
         public async Task ListsMembers_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.GetAsync<TwitterUsers>(
                     new Uri("lists/members.json", UriKind.Relative),
@@ -572,7 +572,7 @@ public async Task ListsMembers_Test()
         [Fact]
         public async Task ListsMembersShow_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.GetAsync<TwitterUser>(
                     new Uri("lists/members/show.json", UriKind.Relative),
@@ -599,7 +599,7 @@ public async Task ListsMembersShow_Test()
         [Fact]
         public async Task ListsMembersCreate_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.PostLazyAsync<TwitterUser>(
                     new Uri("lists/members/create.json", UriKind.Relative),
@@ -626,7 +626,7 @@ await twitterApi.ListsMembersCreate(12345L, "twitterapi")
         [Fact]
         public async Task ListsMembersDestroy_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.PostLazyAsync<TwitterUser>(
                     new Uri("lists/members/destroy.json", UriKind.Relative),
@@ -653,7 +653,7 @@ await twitterApi.ListsMembersDestroy(12345L, "twitterapi")
         [Fact]
         public async Task DirectMessagesEventsList_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.GetAsync<TwitterMessageEventList>(
                     new Uri("direct_messages/events/list.json", UriKind.Relative),
@@ -677,7 +677,7 @@ public async Task DirectMessagesEventsList_Test()
         [Fact]
         public async Task DirectMessagesEventsNew_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             var responseText = """
                 {
                   "event": {
@@ -717,7 +717,7 @@ public async Task DirectMessagesEventsNew_Test()
         [Fact]
         public async Task DirectMessagesEventsDestroy_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.DeleteAsync(
                     new Uri("direct_messages/events/destroy.json?id=100", UriKind.Relative))
@@ -735,7 +735,7 @@ public async Task DirectMessagesEventsDestroy_Test()
         [Fact]
         public async Task UsersShow_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.GetAsync<TwitterUser>(
                     new Uri("users/show.json", UriKind.Relative),
@@ -761,7 +761,7 @@ public async Task UsersShow_Test()
         [Fact]
         public async Task UsersLookup_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.GetAsync<TwitterUser[]>(
                     new Uri("users/lookup.json", UriKind.Relative),
@@ -787,7 +787,7 @@ public async Task UsersLookup_Test()
         [Fact]
         public async Task UsersReportSpam_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.PostLazyAsync<TwitterUser>(
                     new Uri("users/report_spam.json", UriKind.Relative),
@@ -811,7 +811,7 @@ await twitterApi.UsersReportSpam(screenName: "twitterapi")
         [Fact]
         public async Task FavoritesList_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.GetAsync<TwitterStatus[]>(
                     new Uri("favorites/list.json", UriKind.Relative),
@@ -839,7 +839,7 @@ public async Task FavoritesList_Test()
         [Fact]
         public async Task FavoritesCreate_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.PostLazyAsync<TwitterStatus>(
                     new Uri("favorites/create.json", UriKind.Relative),
@@ -863,7 +863,7 @@ public async Task FavoritesCreate_Test()
         [Fact]
         public async Task FavoritesDestroy_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.PostLazyAsync<TwitterStatus>(
                     new Uri("favorites/destroy.json", UriKind.Relative),
@@ -887,7 +887,7 @@ public async Task FavoritesDestroy_Test()
         [Fact]
         public async Task FriendshipsShow_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.GetAsync<TwitterFriendship>(
                     new Uri("friendships/show.json", UriKind.Relative),
@@ -907,7 +907,7 @@ public async Task FriendshipsShow_Test()
         [Fact]
         public async Task FriendshipsCreate_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.PostLazyAsync<TwitterFriendship>(
                     new Uri("friendships/create.json", UriKind.Relative),
@@ -927,7 +927,7 @@ await twitterApi.FriendshipsCreate(screenName: "twitterapi")
         [Fact]
         public async Task FriendshipsDestroy_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.PostLazyAsync<TwitterFriendship>(
                     new Uri("friendships/destroy.json", UriKind.Relative),
@@ -947,7 +947,7 @@ await twitterApi.FriendshipsDestroy(screenName: "twitterapi")
         [Fact]
         public async Task NoRetweetIds_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.GetAsync<long[]>(
                     new Uri("friendships/no_retweets/ids.json", UriKind.Relative),
@@ -967,7 +967,7 @@ public async Task NoRetweetIds_Test()
         [Fact]
         public async Task FollowersIds_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.GetAsync<TwitterIds>(
                     new Uri("followers/ids.json", UriKind.Relative),
@@ -987,7 +987,7 @@ public async Task FollowersIds_Test()
         [Fact]
         public async Task MutesUsersIds_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.GetAsync<TwitterIds>(
                     new Uri("mutes/users/ids.json", UriKind.Relative),
@@ -1007,7 +1007,7 @@ public async Task MutesUsersIds_Test()
         [Fact]
         public async Task BlocksIds_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.GetAsync<TwitterIds>(
                     new Uri("blocks/ids.json", UriKind.Relative),
@@ -1027,7 +1027,7 @@ public async Task BlocksIds_Test()
         [Fact]
         public async Task BlocksCreate_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.PostLazyAsync<TwitterUser>(
                     new Uri("blocks/create.json", UriKind.Relative),
@@ -1051,7 +1051,7 @@ await twitterApi.BlocksCreate(screenName: "twitterapi")
         [Fact]
         public async Task BlocksDestroy_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.PostLazyAsync<TwitterUser>(
                     new Uri("blocks/destroy.json", UriKind.Relative),
@@ -1075,7 +1075,7 @@ await twitterApi.BlocksDestroy(screenName: "twitterapi")
         [Fact]
         public async Task AccountVerifyCredentials_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.GetAsync<TwitterUser>(
                     new Uri("account/verify_credentials.json", UriKind.Relative),
@@ -1107,7 +1107,7 @@ public async Task AccountVerifyCredentials_Test()
         [Fact]
         public async Task AccountUpdateProfile_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.PostLazyAsync<TwitterUser>(
                     new Uri("account/update_profile.json", UriKind.Relative),
@@ -1138,7 +1138,7 @@ public async Task AccountUpdateProfileImage_Test()
         {
             using var image = TestUtils.CreateDummyImage();
             using var media = new MemoryImageMediaItem(image);
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.PostLazyAsync<TwitterUser>(
                     new Uri("account/update_profile_image.json", UriKind.Relative),
@@ -1164,7 +1164,7 @@ await twitterApi.AccountUpdateProfileImage(media)
         [Fact]
         public async Task ApplicationRateLimitStatus_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.GetAsync<TwitterRateLimits>(
                     new Uri("application/rate_limit_status.json", UriKind.Relative),
@@ -1184,7 +1184,7 @@ public async Task ApplicationRateLimitStatus_Test()
         [Fact]
         public async Task Configuration_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.GetAsync<TwitterConfiguration>(
                     new Uri("help/configuration.json", UriKind.Relative),
@@ -1204,7 +1204,7 @@ public async Task Configuration_Test()
         [Fact]
         public async Task MediaUploadInit_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.PostLazyAsync<TwitterUploadMediaInit>(
                     new Uri("https://upload.twitter.com/1.1/media/upload.json", UriKind.Absolute),
@@ -1232,7 +1232,7 @@ public async Task MediaUploadAppend_Test()
         {
             using var image = TestUtils.CreateDummyImage();
             using var media = new MemoryImageMediaItem(image);
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.PostAsync(
                     new Uri("https://upload.twitter.com/1.1/media/upload.json", UriKind.Absolute),
@@ -1257,7 +1257,7 @@ public async Task MediaUploadAppend_Test()
         [Fact]
         public async Task MediaUploadFinalize_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.PostLazyAsync<TwitterUploadMediaResult>(
                     new Uri("https://upload.twitter.com/1.1/media/upload.json", UriKind.Absolute),
@@ -1281,7 +1281,7 @@ await twitterApi.MediaUploadFinalize(mediaId: 11111L)
         [Fact]
         public async Task MediaUploadStatus_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.GetAsync<TwitterUploadMediaResult>(
                     new Uri("https://upload.twitter.com/1.1/media/upload.json", UriKind.Absolute),
@@ -1305,7 +1305,7 @@ public async Task MediaUploadStatus_Test()
         [Fact]
         public async Task MediaMetadataCreate_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.PostJsonAsync(
                     new Uri("https://upload.twitter.com/1.1/media/metadata/create.json", UriKind.Absolute),
diff --git a/OpenTween.Tests/Api/TwitterV2/GetTimelineRequestTest.cs b/OpenTween.Tests/Api/TwitterV2/GetTimelineRequestTest.cs
index fcf5adfdd..a2b00fd96 100644
--- a/OpenTween.Tests/Api/TwitterV2/GetTimelineRequestTest.cs
+++ b/OpenTween.Tests/Api/TwitterV2/GetTimelineRequestTest.cs
@@ -34,7 +34,7 @@ public class GetTimelineRequestTest
         [Fact]
         public async Task StatusesMentionsTimeline_Test()
         {
-            var mock = new Mock<IApiConnection>();
+            var mock = new Mock<IApiConnectionLegacy>();
             mock.Setup(x =>
                 x.GetAsync<TwitterV2TweetIds>(
                     new Uri("/2/users/100/timelines/reverse_chronological", UriKind.Relative),
diff --git a/OpenTween.Tests/Connection/ApiResponseTest.cs b/OpenTween.Tests/Connection/ApiResponseTest.cs
new file mode 100644
index 000000000..a1ff5eee1
--- /dev/null
+++ b/OpenTween.Tests/Connection/ApiResponseTest.cs
@@ -0,0 +1,119 @@
+// OpenTween - Client of Twitter
+// Copyright (c) 2023 kim_upsilon (@kim_upsilon) <https://upsilo.net/~upsilon/>
+// All rights reserved.
+//
+// This file is part of OpenTween.
+//
+// This program is free software; you can redistribute it and/or modify it
+// under the terms of the GNU General Public License as published by the Free
+// Software Foundation; either version 3 of the License, or (at your option)
+// any later version.
+//
+// This program is distributed in the hope that it will be useful, but
+// WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+// or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+// for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this program. If not, see <http://www.gnu.org/licenses/>, or write to
+// the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
+// Boston, MA 02110-1301, USA.
+
+using System.Net;
+using System.Net.Http;
+using System.Runtime.Serialization;
+using System.Threading.Tasks;
+using System.Xml.Linq;
+using OpenTween.Api;
+using Xunit;
+
+namespace OpenTween.Connection
+{
+    public class ApiResponseTest
+    {
+        [Fact]
+        public async Task ReadAsBytes_Test()
+        {
+            using var responseContent = new ByteArrayContent(new byte[] { 1, 2, 3 });
+            using var responseMessage = new HttpResponseMessage
+            {
+                StatusCode = HttpStatusCode.OK,
+                Content = responseContent,
+            };
+            using var response = new ApiResponse(responseMessage);
+
+            Assert.Equal(new byte[] { 1, 2, 3 }, await response.ReadAsBytes());
+        }
+
+        [DataContract]
+        public struct TestJson
+        {
+            [DataMember(Name = "foo")]
+            public int Foo { get; set; }
+        }
+
+        [Fact]
+        public async Task ReadAsJson_Test()
+        {
+            using var responseContent = new StringContent("""{"foo":123}""");
+            using var responseMessage = new HttpResponseMessage
+            {
+                StatusCode = HttpStatusCode.OK,
+                Content = responseContent,
+            };
+            using var response = new ApiResponse(responseMessage);
+
+            Assert.Equal(new() { Foo = 123 }, await response.ReadAsJson<TestJson>());
+        }
+
+        [Fact]
+        public async Task ReadAsJson_InvalidJsonTest()
+        {
+            using var responseContent = new StringContent("### Invalid JSON Response ###");
+            using var responseMessage = new HttpResponseMessage
+            {
+                StatusCode = HttpStatusCode.OK,
+                Content = responseContent,
+            };
+            using var response = new ApiResponse(responseMessage);
+
+            var ex = await Assert.ThrowsAsync<TwitterApiException>(
+                () => response.ReadAsJson<TestJson>()
+            );
+            Assert.Equal("### Invalid JSON Response ###", ex.ResponseText);
+        }
+
+        [Fact]
+        public async Task ReadAsJsonXml_Test()
+        {
+            using var responseContent = new StringContent("""{"foo":123}""");
+            using var responseMessage = new HttpResponseMessage
+            {
+                StatusCode = HttpStatusCode.OK,
+                Content = responseContent,
+            };
+            using var response = new ApiResponse(responseMessage);
+
+            var rootElm = await response.ReadAsJsonXml();
+            var xmlString = rootElm.ToString(SaveOptions.DisableFormatting);
+            Assert.Equal("""<root type="object"><foo type="number">123</foo></root>""", xmlString);
+        }
+
+        [Fact]
+        public async Task ReadAsJsonXml_InvalidJsonTest()
+        {
+            using var responseContent = new StringContent("### Invalid JSON Response ###");
+            using var responseMessage = new HttpResponseMessage
+            {
+                StatusCode = HttpStatusCode.OK,
+                Content = responseContent,
+            };
+            using var response = new ApiResponse(responseMessage);
+
+            var ex = await Assert.ThrowsAsync<TwitterApiException>(
+                () => response.ReadAsJsonXml()
+            );
+            Assert.Equal("### Invalid JSON Response ###", ex.ResponseText);
+        }
+    }
+}
diff --git a/OpenTween.Tests/Connection/GetRequestTest.cs b/OpenTween.Tests/Connection/GetRequestTest.cs
new file mode 100644
index 000000000..db738b66f
--- /dev/null
+++ b/OpenTween.Tests/Connection/GetRequestTest.cs
@@ -0,0 +1,81 @@
+// OpenTween - Client of Twitter
+// Copyright (c) 2023 kim_upsilon (@kim_upsilon) <https://upsilo.net/~upsilon/>
+// All rights reserved.
+//
+// This file is part of OpenTween.
+//
+// This program is free software; you can redistribute it and/or modify it
+// under the terms of the GNU General Public License as published by the Free
+// Software Foundation; either version 3 of the License, or (at your option)
+// any later version.
+//
+// This program is distributed in the hope that it will be useful, but
+// WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+// or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+// for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this program. If not, see <http://www.gnu.org/licenses/>, or write to
+// the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
+// Boston, MA 02110-1301, USA.
+
+using System;
+using System.Collections.Generic;
+using System.Net.Http;
+using Xunit;
+
+namespace OpenTween.Connection
+{
+    public class GetRequestTest
+    {
+        [Fact]
+        public void CreateMessage_Test()
+        {
+            var request = new GetRequest
+            {
+                RequestUri = new("statuses/show.json", UriKind.Relative),
+                Query = new Dictionary<string, string>
+                {
+                    ["id"] = "12345",
+                },
+            };
+
+            var baseUri = new Uri("https://api.twitter.com/v1/");
+            using var requestMessage = request.CreateMessage(baseUri);
+
+            Assert.Equal(HttpMethod.Get, requestMessage.Method);
+            Assert.Equal(new("https://api.twitter.com/v1/statuses/show.json?id=12345"), requestMessage.RequestUri);
+        }
+
+        [Fact]
+        public void BuildUriWithQuery_Test()
+        {
+            var uri = new Uri("https://example.com/hoge");
+            var query = new Dictionary<string, string>
+            {
+                ["foo"] = "bar",
+            };
+            Assert.Equal(new("https://example.com/hoge?foo=bar"), GetRequest.BuildUriWithQuery(uri, query));
+        }
+
+        [Fact]
+        public void BuildUriWithQuery_NullTest()
+        {
+            var uri = new Uri("https://example.com/hoge");
+            Assert.Equal(new("https://example.com/hoge"), GetRequest.BuildUriWithQuery(uri, null));
+        }
+
+        [Fact]
+        public void BuildUriWithQuery_CannotMergeTest()
+        {
+            var uri = new Uri("https://example.com/hoge?aaa=111");
+            var query = new Dictionary<string, string>
+            {
+                ["bbb"] = "222",
+            };
+            Assert.Throws<NotSupportedException>(
+                () => GetRequest.BuildUriWithQuery(uri, query)
+            );
+        }
+    }
+}
diff --git a/OpenTween.Tests/Connection/TwitterApiConnectionTest.cs b/OpenTween.Tests/Connection/TwitterApiConnectionTest.cs
index 929f45eb1..1c7b53cdf 100644
--- a/OpenTween.Tests/Connection/TwitterApiConnectionTest.cs
+++ b/OpenTween.Tests/Connection/TwitterApiConnectionTest.cs
@@ -29,6 +29,7 @@
 using System.Reflection;
 using System.Runtime.InteropServices;
 using System.Text;
+using System.Threading;
 using System.Threading.Tasks;
 using System.Web;
 using Moq;
@@ -127,7 +128,50 @@ public async Task GetAsync_AbsoluteUriTest()
         }
 
         [Fact]
-        public async Task GetAsync_UpdateRateLimitTest()
+        public async Task SendAsync_Test()
+        {
+            using var mockHandler = new HttpMessageHandlerMock();
+            using var http = new HttpClient(mockHandler);
+            using var apiConnection = new TwitterApiConnection(ApiKey.Create(""), ApiKey.Create(""), "", "");
+            apiConnection.Http = http;
+
+            mockHandler.Enqueue(x =>
+            {
+                Assert.Equal(HttpMethod.Get, x.Method);
+                Assert.Equal("https://api.twitter.com/1.1/hoge/tetete.json",
+                    x.RequestUri.GetLeftPart(UriPartial.Path));
+
+                var query = HttpUtility.ParseQueryString(x.RequestUri.Query);
+
+                Assert.Equal("1111", query["aaaa"]);
+                Assert.Equal("2222", query["bbbb"]);
+
+                return new HttpResponseMessage(HttpStatusCode.OK)
+                {
+                    Content = new StringContent("\"hogehoge\""),
+                };
+            });
+
+            var request = new GetRequest
+            {
+                RequestUri = new("hoge/tetete.json", UriKind.Relative),
+                Query = new Dictionary<string, string>
+                {
+                    ["aaaa"] = "1111",
+                    ["bbbb"] = "2222",
+                },
+                EndpointName = "/hoge/tetete",
+            };
+
+            using var response = await apiConnection.SendAsync(request);
+
+            Assert.Equal("hogehoge", await response.ReadAsJson<string>());
+
+            Assert.Equal(0, mockHandler.QueueCount);
+        }
+
+        [Fact]
+        public async Task SendAsync_UpdateRateLimitTest()
         {
             using var mockHandler = new HttpMessageHandlerMock();
             using var http = new HttpClient(mockHandler);
@@ -144,10 +188,10 @@ public async Task GetAsync_UpdateRateLimitTest()
                 {
                     Headers =
                     {
-                            { "X-Rate-Limit-Limit", "150" },
-                            { "X-Rate-Limit-Remaining", "100" },
-                            { "X-Rate-Limit-Reset", "1356998400" },
-                            { "X-Access-Level", "read-write-directmessages" },
+                        { "X-Rate-Limit-Limit", "150" },
+                        { "X-Rate-Limit-Remaining", "100" },
+                        { "X-Rate-Limit-Reset", "1356998400" },
+                        { "X-Access-Level", "read-write-directmessages" },
                     },
                     Content = new StringContent("\"hogehoge\""),
                 };
@@ -156,9 +200,13 @@ public async Task GetAsync_UpdateRateLimitTest()
             var apiStatus = new TwitterApiStatus();
             MyCommon.TwitterApiInfo = apiStatus;
 
-            var endpoint = new Uri("hoge/tetete.json", UriKind.Relative);
+            var request = new GetRequest
+            {
+                RequestUri = new("hoge/tetete.json", UriKind.Relative),
+                EndpointName = "/hoge/tetete",
+            };
 
-            await apiConnection.GetAsync<string>(endpoint, null, endpointName: "/hoge/tetete");
+            using var response = await apiConnection.SendAsync(request);
 
             Assert.Equal(TwitterApiAccessLevel.ReadWriteAndDirectMessage, apiStatus.AccessLevel);
             Assert.Equal(new ApiLimit(150, 100, new DateTimeUtc(2013, 1, 1, 0, 0, 0)), apiStatus.AccessLimit["/hoge/tetete"]);
@@ -167,7 +215,7 @@ public async Task GetAsync_UpdateRateLimitTest()
         }
 
         [Fact]
-        public async Task GetAsync_ErrorStatusTest()
+        public async Task SendAsync_ErrorStatusTest()
         {
             using var mockHandler = new HttpMessageHandlerMock();
             using var http = new HttpClient(mockHandler);
@@ -182,10 +230,13 @@ public async Task GetAsync_ErrorStatusTest()
                 };
             });
 
-            var endpoint = new Uri("hoge/tetete.json", UriKind.Relative);
+            var request = new GetRequest
+            {
+                RequestUri = new("hoge/tetete.json", UriKind.Relative),
+            };
 
             var exception = await Assert.ThrowsAsync<TwitterApiException>(
-                () => apiConnection.GetAsync<string>(endpoint, null, endpointName: "/hoge/tetete")
+                () => apiConnection.SendAsync(request)
             );
 
             // エラーレスポンスの読み込みに失敗した場合はステータスコードをそのままメッセージに使用する
@@ -196,7 +247,7 @@ public async Task GetAsync_ErrorStatusTest()
         }
 
         [Fact]
-        public async Task GetAsync_ErrorJsonTest()
+        public async Task SendAsync_ErrorJsonTest()
         {
             using var mockHandler = new HttpMessageHandlerMock();
             using var http = new HttpClient(mockHandler);
@@ -211,10 +262,13 @@ public async Task GetAsync_ErrorJsonTest()
                 };
             });
 
-            var endpoint = new Uri("hoge/tetete.json", UriKind.Relative);
+            var request = new GetRequest
+            {
+                RequestUri = new("hoge/tetete.json", UriKind.Relative),
+            };
 
             var exception = await Assert.ThrowsAsync<TwitterApiException>(
-                () => apiConnection.GetAsync<string>(endpoint, null, endpointName: "/hoge/tetete")
+                () => apiConnection.SendAsync(request)
             );
 
             // エラーレスポンスの JSON に含まれるエラーコードに基づいてメッセージを出力する
@@ -519,5 +573,76 @@ public async Task DeleteAsync_Test()
 
             Assert.Equal(0, mockHandler.QueueCount);
         }
+
+        [Fact]
+        public async Task HandleTimeout_SuccessTest()
+        {
+            static async Task<int> AsyncFunc(CancellationToken token)
+            {
+                await Task.Delay(10);
+                token.ThrowIfCancellationRequested();
+                return 1;
+            }
+
+            var timeout = TimeSpan.FromMilliseconds(200);
+            var ret = await TwitterApiConnection.HandleTimeout(AsyncFunc, timeout);
+
+            Assert.Equal(1, ret);
+        }
+
+        [Fact]
+        public async Task HandleTimeout_TimeoutTest()
+        {
+            var tcs = new TaskCompletionSource<bool>();
+
+            async Task<int> AsyncFunc(CancellationToken token)
+            {
+                await Task.Delay(200);
+                tcs.SetResult(token.IsCancellationRequested);
+                return 1;
+            }
+
+            var timeout = TimeSpan.FromMilliseconds(10);
+            await Assert.ThrowsAsync<OperationCanceledException>(
+                () => TwitterApiConnection.HandleTimeout(AsyncFunc, timeout)
+            );
+
+            var cancelRequested = await tcs.Task;
+            Assert.True(cancelRequested);
+        }
+
+        [Fact]
+        public async Task HandleTimeout_ThrowExceptionAfterTimeoutTest()
+        {
+            var tcs = new TaskCompletionSource<int>();
+
+            async Task<int> AsyncFunc(CancellationToken token)
+            {
+                await Task.Delay(100);
+                tcs.SetResult(1);
+                throw new Exception();
+            }
+
+            var timeout = TimeSpan.FromMilliseconds(10);
+            await Assert.ThrowsAsync<OperationCanceledException>(
+                () => TwitterApiConnection.HandleTimeout(AsyncFunc, timeout)
+            );
+
+            // キャンセル後に AsyncFunc で発生した例外が無視される（UnobservedTaskException イベントを発生させない）ことをチェックする
+            var error = false;
+            void UnobservedExceptionHandler(object s, UnobservedTaskExceptionEventArgs e)
+                => error = true;
+
+            TaskScheduler.UnobservedTaskException += UnobservedExceptionHandler;
+
+            await tcs.Task;
+            await Task.Delay(10);
+            GC.Collect(); // UnobservedTaskException は Task のデストラクタで呼ばれるため強制的に GC を実行する
+            await Task.Delay(10);
+
+            Assert.False(error);
+
+            TaskScheduler.UnobservedTaskException -= UnobservedExceptionHandler;
+        }
     }
 }
diff --git a/OpenTween.Tests/MyCommonTest.cs b/OpenTween.Tests/MyCommonTest.cs
index 560c6a82b..1261d4730 100644
--- a/OpenTween.Tests/MyCommonTest.cs
+++ b/OpenTween.Tests/MyCommonTest.cs
@@ -135,9 +135,17 @@ public struct JsonData
 
         [Theory]
         [MemberData(nameof(CreateDataFromJsonTestCase))]
-        public void CreateDataFromJsonTest<T>(string json, T expected)
+        public void CreateDataFromJson_StringTest<T>(string json, T expected)
             => Assert.Equal(expected, MyCommon.CreateDataFromJson<T>(json));
 
+        [Theory]
+        [MemberData(nameof(CreateDataFromJsonTestCase))]
+        public void CreateDataFromJson_BytesTest<T>(string json, T expected)
+        {
+            var jsonBytes = Encoding.UTF8.GetBytes(json);
+            Assert.Equal(expected, MyCommon.CreateDataFromJson<T>(jsonBytes));
+        }
+
         [Theory]
         [InlineData("hoge123@example.com", true)]
         [InlineData("hogehoge", false)]
diff --git a/OpenTween.Tests/TestUtils.cs b/OpenTween.Tests/TestUtils.cs
index c1c4e8869..9d5848a84 100644
--- a/OpenTween.Tests/TestUtils.cs
+++ b/OpenTween.Tests/TestUtils.cs
@@ -20,16 +20,16 @@
 // Boston, MA 02110-1301, USA.
 
 using System;
-using System.Collections.Generic;
 using System.ComponentModel;
 using System.Drawing;
 using System.Drawing.Imaging;
 using System.IO;
-using System.Linq;
+using System.Net;
+using System.Net.Http;
 using System.Reflection;
-using System.Text;
 using System.Threading.Tasks;
 using System.Windows.Forms;
+using OpenTween.Connection;
 using Xunit;
 
 namespace OpenTween
@@ -152,6 +152,22 @@ public void Dispose()
 
         public static DateTimeUtc LocalTime(int year, int month, int day, int hour, int minute, int second)
             => new(new DateTimeOffset(year, month, day, hour, minute, second, TimeZoneInfo.Local.BaseUtcOffset));
+
+        public static async Task<ApiResponse> CreateApiResponse(string path)
+        {
+            byte[] buffer;
+            using (var stream = new FileStream(path, FileMode.Open, FileAccess.Read))
+            {
+                buffer = new byte[stream.Length];
+                await stream.ReadAsync(buffer, 0, buffer.Length);
+            }
+            var responseMessage = new HttpResponseMessage
+            {
+                StatusCode = HttpStatusCode.OK,
+                Content = new ByteArrayContent(buffer),
+            };
+            return new ApiResponse(responseMessage);
+        }
     }
 }
 
diff --git a/OpenTween.Tests/Thumbnail/Services/TonTwitterComTest.cs b/OpenTween.Tests/Thumbnail/Services/TonTwitterComTest.cs
new file mode 100644
index 000000000..235c9c823
--- /dev/null
+++ b/OpenTween.Tests/Thumbnail/Services/TonTwitterComTest.cs
@@ -0,0 +1,135 @@
+// OpenTween - Client of Twitter
+// Copyright (c) 2023 kim_upsilon (@kim_upsilon) <https://upsilo.net/~upsilon/>
+// All rights reserved.
+//
+// This file is part of OpenTween.
+//
+// This program is free software; you can redistribute it and/or modify it
+// under the terms of the GNU General Public License as published by the Free
+// Software Foundation; either version 3 of the License, or (at your option)
+// any later version.
+//
+// This program is distributed in the hope that it will be useful, but
+// WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+// or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+// for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this program. If not, see <http://www.gnu.org/licenses/>, or write to
+// the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
+// Boston, MA 02110-1301, USA.
+
+using System.Net;
+using System.Net.Http;
+using System.Threading;
+using System.Threading.Tasks;
+using Moq;
+using OpenTween.Connection;
+using Xunit;
+
+namespace OpenTween.Thumbnail.Services
+{
+    public class TonTwitterComTest
+    {
+        [Fact]
+        public async Task GetThumbnailInfoAsync_Test()
+        {
+            var mock = new Mock<IApiConnection>();
+            TonTwitterCom.GetApiConnection = () => mock.Object;
+
+            var service = new TonTwitterCom();
+            var thumb = await service.GetThumbnailInfoAsync(
+                "https://ton.twitter.com/1.1/ton/data/dm/123456/123456/abcdef.jpg",
+                new(),
+                CancellationToken.None
+            );
+
+            Assert.NotNull(thumb!);
+            Assert.Equal(
+                "https://ton.twitter.com/1.1/ton/data/dm/123456/123456/abcdef.jpg:large",
+                thumb.MediaPageUrl
+            );
+            Assert.Equal(
+                "https://ton.twitter.com/1.1/ton/data/dm/123456/123456/abcdef.jpg:large",
+                thumb.FullSizeImageUrl
+            );
+            Assert.Equal(
+                "https://ton.twitter.com/1.1/ton/data/dm/123456/123456/abcdef.jpg",
+                thumb.ThumbnailImageUrl
+            );
+
+            TonTwitterCom.GetApiConnection = null;
+        }
+
+        [Fact]
+        public async Task GetThumbnailInfoAsync_ApiConnectionIsNotSetTest()
+        {
+            TonTwitterCom.GetApiConnection = null;
+
+            var service = new TonTwitterCom();
+            var thumb = await service.GetThumbnailInfoAsync(
+                "https://ton.twitter.com/1.1/ton/data/dm/123456/123456/abcdef.jpg",
+                new(),
+                CancellationToken.None
+            );
+
+            Assert.Null(thumb);
+        }
+
+        [Fact]
+        public async Task GetThumbnailInfoAsync_NotMatchedTest()
+        {
+            var mock = new Mock<IApiConnection>();
+            TonTwitterCom.GetApiConnection = () => mock.Object;
+
+            var service = new TonTwitterCom();
+            var thumb = await service.GetThumbnailInfoAsync(
+                "https://example.com/abcdef.jpg",
+                new(),
+                CancellationToken.None
+            );
+
+            Assert.Null(thumb);
+
+            TonTwitterCom.GetApiConnection = null;
+        }
+
+        [Fact]
+        public async Task LoadThumbnailImageAsync_Test()
+        {
+            using var image = TestUtils.CreateDummyImage();
+            using var responseMessage = new HttpResponseMessage(HttpStatusCode.OK)
+            {
+                Content = new ByteArrayContent(image.Stream.ToArray()),
+            };
+            using var response = new ApiResponse(responseMessage);
+
+            var mock = new Mock<IApiConnection>();
+            mock.Setup(
+                    x => x.SendAsync(It.IsAny<IHttpRequest>())
+                )
+                .Callback<IHttpRequest>(x =>
+                {
+                    var request = Assert.IsType<GetRequest>(x);
+                    Assert.Equal(
+                        new("https://ton.twitter.com/1.1/ton/data/dm/123456/123456/abcdef.jpg"),
+                        request.RequestUri
+                    );
+                })
+                .ReturnsAsync(response);
+
+            var apiConnection = mock.Object;
+            var thumb = new TonTwitterCom.Thumbnail(apiConnection)
+            {
+                MediaPageUrl = "https://ton.twitter.com/1.1/ton/data/dm/123456/123456/abcdef.jpg:large",
+                FullSizeImageUrl = "https://ton.twitter.com/1.1/ton/data/dm/123456/123456/abcdef.jpg:large",
+                ThumbnailImageUrl = "https://ton.twitter.com/1.1/ton/data/dm/123456/123456/abcdef.jpg",
+            };
+
+            var result = await thumb.LoadThumbnailImageAsync(CancellationToken.None);
+            Assert.Equal(image, result);
+
+            mock.VerifyAll();
+        }
+    }
+}
diff --git a/OpenTween/Api/GraphQL/CreateRetweetRequest.cs b/OpenTween/Api/GraphQL/CreateRetweetRequest.cs
index 33c579df2..35b5060e2 100644
--- a/OpenTween/Api/GraphQL/CreateRetweetRequest.cs
+++ b/OpenTween/Api/GraphQL/CreateRetweetRequest.cs
@@ -49,7 +49,7 @@ public string CreateRequestBody()
             """;
         }
 
-        public async Task<TwitterStatusId> Send(IApiConnection apiConnection)
+        public async Task<TwitterStatusId> Send(IApiConnectionLegacy apiConnection)
         {
             var json = this.CreateRequestBody();
             var response = await apiConnection.PostJsonAsync(EndpointUri, json);
diff --git a/OpenTween/Api/GraphQL/CreateTweetRequest.cs b/OpenTween/Api/GraphQL/CreateTweetRequest.cs
index d2b0f229c..46e1075ac 100644
--- a/OpenTween/Api/GraphQL/CreateTweetRequest.cs
+++ b/OpenTween/Api/GraphQL/CreateTweetRequest.cs
@@ -153,7 +153,7 @@ public string CreateRequestBody()
             return JsonUtils.SerializeJsonByDataContract(body);
         }
 
-        public async Task<TwitterStatus> Send(IApiConnection apiConnection)
+        public async Task<TwitterStatus> Send(IApiConnectionLegacy apiConnection)
         {
             var json = this.CreateRequestBody();
             var response = await apiConnection.PostJsonAsync(EndpointUri, json);
diff --git a/OpenTween/Api/GraphQL/DeleteRetweetRequest.cs b/OpenTween/Api/GraphQL/DeleteRetweetRequest.cs
index ab5b0aedc..00a0b8368 100644
--- a/OpenTween/Api/GraphQL/DeleteRetweetRequest.cs
+++ b/OpenTween/Api/GraphQL/DeleteRetweetRequest.cs
@@ -45,7 +45,7 @@ public string CreateRequestBody()
             """;
         }
 
-        public async Task Send(IApiConnection apiConnection)
+        public async Task Send(IApiConnectionLegacy apiConnection)
         {
             var json = this.CreateRequestBody();
             var responseText = await apiConnection.PostJsonAsync(EndpointUri, json);
diff --git a/OpenTween/Api/GraphQL/DeleteTweetRequest.cs b/OpenTween/Api/GraphQL/DeleteTweetRequest.cs
index feeee14eb..adccacec0 100644
--- a/OpenTween/Api/GraphQL/DeleteTweetRequest.cs
+++ b/OpenTween/Api/GraphQL/DeleteTweetRequest.cs
@@ -45,7 +45,7 @@ public string CreateRequestBody()
             """;
         }
 
-        public async Task Send(IApiConnection apiConnection)
+        public async Task Send(IApiConnectionLegacy apiConnection)
         {
             var json = this.CreateRequestBody();
             var responseText = await apiConnection.PostJsonAsync(EndpointUri, json);
diff --git a/OpenTween/Api/GraphQL/ListLatestTweetsTimelineRequest.cs b/OpenTween/Api/GraphQL/ListLatestTweetsTimelineRequest.cs
index a241e4a86..3aa306f6f 100644
--- a/OpenTween/Api/GraphQL/ListLatestTweetsTimelineRequest.cs
+++ b/OpenTween/Api/GraphQL/ListLatestTweetsTimelineRequest.cs
@@ -23,13 +23,7 @@
 
 using System;
 using System.Collections.Generic;
-using System.IO;
-using System.Linq;
-using System.Runtime.Serialization.Json;
-using System.Text;
 using System.Threading.Tasks;
-using System.Xml;
-using System.Xml.Linq;
 using System.Xml.XPath;
 using OpenTween.Connection;
 
@@ -86,24 +80,18 @@ public Dictionary<string, string> CreateParameters()
 
         public async Task<TimelineResponse> Send(IApiConnection apiConnection)
         {
-            var param = this.CreateParameters();
-
-            XElement rootElm;
-            try
-            {
-                using var stream = await apiConnection.GetStreamAsync(EndpointUri, param, EndpointName);
-                using var jsonReader = JsonReaderWriterFactory.CreateJsonReader(stream, XmlDictionaryReaderQuotas.Max);
-                rootElm = XElement.Load(jsonReader);
-            }
-            catch (IOException ex)
-            {
-                throw new WebApiException("IO Error", ex);
-            }
-            catch (NotSupportedException ex)
+            var request = new GetRequest
             {
-                // NotSupportedException: Stream does not support reading. のエラーが時々報告される
-                throw new WebApiException("Stream Error", ex);
-            }
+                RequestUri = EndpointUri,
+                Query = this.CreateParameters(),
+                EndpointName = EndpointName,
+            };
+
+            using var response = await apiConnection.SendAsync(request)
+                .ConfigureAwait(false);
+
+            var rootElm = await response.ReadAsJsonXml()
+                .ConfigureAwait(false);
 
             ErrorResponse.ThrowIfError(rootElm);
 
diff --git a/OpenTween/Api/GraphQL/SearchTimelineRequest.cs b/OpenTween/Api/GraphQL/SearchTimelineRequest.cs
index 9e76ca05b..568371806 100644
--- a/OpenTween/Api/GraphQL/SearchTimelineRequest.cs
+++ b/OpenTween/Api/GraphQL/SearchTimelineRequest.cs
@@ -23,13 +23,7 @@
 
 using System;
 using System.Collections.Generic;
-using System.IO;
-using System.Linq;
-using System.Runtime.Serialization.Json;
-using System.Text;
 using System.Threading.Tasks;
-using System.Xml;
-using System.Xml.Linq;
 using System.Xml.XPath;
 using OpenTween.Connection;
 
@@ -88,24 +82,18 @@ public Dictionary<string, string> CreateParameters()
 
         public async Task<TimelineResponse> Send(IApiConnection apiConnection)
         {
-            var param = this.CreateParameters();
-
-            XElement rootElm;
-            try
-            {
-                using var stream = await apiConnection.GetStreamAsync(EndpointUri, param, EndpointName);
-                using var jsonReader = JsonReaderWriterFactory.CreateJsonReader(stream, XmlDictionaryReaderQuotas.Max);
-                rootElm = XElement.Load(jsonReader);
-            }
-            catch (IOException ex)
-            {
-                throw new WebApiException("IO Error", ex);
-            }
-            catch (NotSupportedException ex)
+            var request = new GetRequest
             {
-                // NotSupportedException: Stream does not support reading. のエラーが時々報告される
-                throw new WebApiException("Stream Error", ex);
-            }
+                RequestUri = EndpointUri,
+                Query = this.CreateParameters(),
+                EndpointName = EndpointName,
+            };
+
+            using var response = await apiConnection.SendAsync(request)
+                .ConfigureAwait(false);
+
+            var rootElm = await response.ReadAsJsonXml()
+                .ConfigureAwait(false);
 
             ErrorResponse.ThrowIfError(rootElm);
 
diff --git a/OpenTween/Api/GraphQL/TweetDetailRequest.cs b/OpenTween/Api/GraphQL/TweetDetailRequest.cs
index 496e2f47c..b8c4151d3 100644
--- a/OpenTween/Api/GraphQL/TweetDetailRequest.cs
+++ b/OpenTween/Api/GraphQL/TweetDetailRequest.cs
@@ -23,14 +23,7 @@
 
 using System;
 using System.Collections.Generic;
-using System.IO;
-using System.Linq;
-using System.Runtime.Serialization.Json;
-using System.Text;
 using System.Threading.Tasks;
-using System.Xml;
-using System.Xml.Linq;
-using System.Xml.XPath;
 using OpenTween.Connection;
 using OpenTween.Models;
 
@@ -62,24 +55,18 @@ public Dictionary<string, string> CreateParameters()
 
         public async Task<TimelineTweet[]> Send(IApiConnection apiConnection)
         {
-            var param = this.CreateParameters();
-
-            XElement rootElm;
-            try
-            {
-                using var stream = await apiConnection.GetStreamAsync(EndpointUri, param, EndpointName);
-                using var jsonReader = JsonReaderWriterFactory.CreateJsonReader(stream, XmlDictionaryReaderQuotas.Max);
-                rootElm = XElement.Load(jsonReader);
-            }
-            catch (IOException ex)
-            {
-                throw new WebApiException("IO Error", ex);
-            }
-            catch (NotSupportedException ex)
+            var request = new GetRequest
             {
-                // NotSupportedException: Stream does not support reading. のエラーが時々報告される
-                throw new WebApiException("Stream Error", ex);
-            }
+                RequestUri = EndpointUri,
+                Query = this.CreateParameters(),
+                EndpointName = EndpointName,
+            };
+
+            using var response = await apiConnection.SendAsync(request)
+                .ConfigureAwait(false);
+
+            var rootElm = await response.ReadAsJsonXml()
+                .ConfigureAwait(false);
 
             ErrorResponse.ThrowIfError(rootElm);
 
diff --git a/OpenTween/Api/GraphQL/UserByScreenNameRequest.cs b/OpenTween/Api/GraphQL/UserByScreenNameRequest.cs
index 8d5607ef5..4b3c8ccad 100644
--- a/OpenTween/Api/GraphQL/UserByScreenNameRequest.cs
+++ b/OpenTween/Api/GraphQL/UserByScreenNameRequest.cs
@@ -23,12 +23,7 @@
 
 using System;
 using System.Collections.Generic;
-using System.IO;
-using System.Linq;
-using System.Runtime.Serialization.Json;
-using System.Text;
 using System.Threading.Tasks;
-using System.Xml;
 using System.Xml.Linq;
 using System.Xml.XPath;
 using OpenTween.Connection;
@@ -61,24 +56,18 @@ public Dictionary<string, string> CreateParameters()
 
         public async Task<TwitterGraphqlUser> Send(IApiConnection apiConnection)
         {
-            var param = this.CreateParameters();
-
-            XElement rootElm;
-            try
-            {
-                using var stream = await apiConnection.GetStreamAsync(EndpointUri, param, EndpointName);
-                using var jsonReader = JsonReaderWriterFactory.CreateJsonReader(stream, XmlDictionaryReaderQuotas.Max);
-                rootElm = XElement.Load(jsonReader);
-            }
-            catch (IOException ex)
-            {
-                throw new WebApiException("IO Error", ex);
-            }
-            catch (NotSupportedException ex)
+            var request = new GetRequest
             {
-                // NotSupportedException: Stream does not support reading. のエラーが時々報告される
-                throw new WebApiException("Stream Error", ex);
-            }
+                RequestUri = EndpointUri,
+                Query = this.CreateParameters(),
+                EndpointName = EndpointName,
+            };
+
+            using var response = await apiConnection.SendAsync(request)
+                .ConfigureAwait(false);
+
+            var rootElm = await response.ReadAsJsonXml()
+                .ConfigureAwait(false);
 
             ErrorResponse.ThrowIfError(rootElm);
 
diff --git a/OpenTween/Api/GraphQL/UserTweetsAndRepliesRequest.cs b/OpenTween/Api/GraphQL/UserTweetsAndRepliesRequest.cs
index 916a914b8..fff651342 100644
--- a/OpenTween/Api/GraphQL/UserTweetsAndRepliesRequest.cs
+++ b/OpenTween/Api/GraphQL/UserTweetsAndRepliesRequest.cs
@@ -23,13 +23,7 @@
 
 using System;
 using System.Collections.Generic;
-using System.IO;
-using System.Linq;
-using System.Runtime.Serialization.Json;
-using System.Text;
 using System.Threading.Tasks;
-using System.Xml;
-using System.Xml.Linq;
 using System.Xml.XPath;
 using OpenTween.Connection;
 
@@ -71,24 +65,18 @@ public Dictionary<string, string> CreateParameters()
 
         public async Task<TimelineResponse> Send(IApiConnection apiConnection)
         {
-            var param = this.CreateParameters();
-
-            XElement rootElm;
-            try
-            {
-                using var stream = await apiConnection.GetStreamAsync(EndpointUri, param, EndpointName);
-                using var jsonReader = JsonReaderWriterFactory.CreateJsonReader(stream, XmlDictionaryReaderQuotas.Max);
-                rootElm = XElement.Load(jsonReader);
-            }
-            catch (IOException ex)
-            {
-                throw new WebApiException("IO Error", ex);
-            }
-            catch (NotSupportedException ex)
+            var request = new GetRequest
             {
-                // NotSupportedException: Stream does not support reading. のエラーが時々報告される
-                throw new WebApiException("Stream Error", ex);
-            }
+                RequestUri = EndpointUri,
+                Query = this.CreateParameters(),
+                EndpointName = EndpointName,
+            };
+
+            using var response = await apiConnection.SendAsync(request)
+                .ConfigureAwait(false);
+
+            var rootElm = await response.ReadAsJsonXml()
+                .ConfigureAwait(false);
 
             ErrorResponse.ThrowIfError(rootElm);
 
diff --git a/OpenTween/Api/TwitterApi.cs b/OpenTween/Api/TwitterApi.cs
index 1f3b68e63..abce76331 100644
--- a/OpenTween/Api/TwitterApi.cs
+++ b/OpenTween/Api/TwitterApi.cs
@@ -41,9 +41,9 @@ public sealed class TwitterApi : IDisposable
 
         public string CurrentScreenName { get; private set; } = "";
 
-        public IApiConnection Connection => this.ApiConnection ?? throw new InvalidOperationException();
+        public IApiConnectionLegacy Connection => this.ApiConnection ?? throw new InvalidOperationException();
 
-        internal IApiConnection? ApiConnection;
+        internal IApiConnectionLegacy? ApiConnection;
 
         public TwitterAppToken AppToken { get; private set; } = TwitterAppToken.GetDefault();
 
diff --git a/OpenTween/Api/TwitterV2/GetTimelineRequest.cs b/OpenTween/Api/TwitterV2/GetTimelineRequest.cs
index 6ff98cf55..677d167ae 100644
--- a/OpenTween/Api/TwitterV2/GetTimelineRequest.cs
+++ b/OpenTween/Api/TwitterV2/GetTimelineRequest.cs
@@ -69,7 +69,7 @@ private Dictionary<string, string> CreateParameters()
             return param;
         }
 
-        public Task<TwitterV2TweetIds> Send(IApiConnection apiConnection)
+        public Task<TwitterV2TweetIds> Send(IApiConnectionLegacy apiConnection)
         {
             var uri = this.CreateEndpointUri();
             var param = this.CreateParameters();
diff --git a/OpenTween/Connection/ApiResponse.cs b/OpenTween/Connection/ApiResponse.cs
new file mode 100644
index 000000000..3eabcb661
--- /dev/null
+++ b/OpenTween/Connection/ApiResponse.cs
@@ -0,0 +1,99 @@
+// OpenTween - Client of Twitter
+// Copyright (c) 2023 kim_upsilon (@kim_upsilon) <https://upsilo.net/~upsilon/>
+// All rights reserved.
+//
+// This file is part of OpenTween.
+//
+// This program is free software; you can redistribute it and/or modify it
+// under the terms of the GNU General Public License as published by the Free
+// Software Foundation; either version 3 of the License, or (at your option)
+// any later version.
+//
+// This program is distributed in the hope that it will be useful, but
+// WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+// or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+// for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this program. If not, see <http://www.gnu.org/licenses/>, or write to
+// the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
+// Boston, MA 02110-1301, USA.
+
+#nullable enable
+
+using System;
+using System.Net.Http;
+using System.Runtime.Serialization;
+using System.Runtime.Serialization.Json;
+using System.Text;
+using System.Threading.Tasks;
+using System.Xml;
+using System.Xml.Linq;
+using OpenTween.Api;
+
+namespace OpenTween.Connection
+{
+    public sealed class ApiResponse : IDisposable
+    {
+        public bool IsDisposed { get; private set; }
+
+        private readonly HttpResponseMessage responseMessage;
+
+        public ApiResponse(HttpResponseMessage responseMessage)
+            => this.responseMessage = responseMessage;
+
+        public void Dispose()
+        {
+            if (this.IsDisposed)
+                return;
+
+            this.responseMessage.Dispose();
+            this.IsDisposed = true;
+        }
+
+        public async Task<byte[]> ReadAsBytes()
+        {
+            using var content = this.responseMessage.Content;
+
+            return await content.ReadAsByteArrayAsync()
+                .ConfigureAwait(false);
+        }
+
+        public async Task<T> ReadAsJson<T>()
+        {
+            var responseBytes = await this.ReadAsBytes()
+                .ConfigureAwait(false);
+
+            try
+            {
+                return MyCommon.CreateDataFromJson<T>(responseBytes);
+            }
+            catch (SerializationException ex)
+            {
+                var responseText = Encoding.UTF8.GetString(responseBytes);
+                throw TwitterApiException.CreateFromException(ex, responseText);
+            }
+        }
+
+        public async Task<XElement> ReadAsJsonXml()
+        {
+            var responseBytes = await this.ReadAsBytes()
+                .ConfigureAwait(false);
+
+            using var jsonReader = JsonReaderWriterFactory.CreateJsonReader(
+                responseBytes,
+                XmlDictionaryReaderQuotas.Max
+            );
+
+            try
+            {
+                return XElement.Load(jsonReader);
+            }
+            catch (XmlException ex)
+            {
+                var responseText = Encoding.UTF8.GetString(responseBytes);
+                throw new TwitterApiException("Invalid JSON", ex) { ResponseText = responseText };
+            }
+        }
+    }
+}
diff --git a/OpenTween/Connection/GetRequest.cs b/OpenTween/Connection/GetRequest.cs
new file mode 100644
index 000000000..018354a13
--- /dev/null
+++ b/OpenTween/Connection/GetRequest.cs
@@ -0,0 +1,56 @@
+// OpenTween - Client of Twitter
+// Copyright (c) 2023 kim_upsilon (@kim_upsilon) <https://upsilo.net/~upsilon/>
+// All rights reserved.
+//
+// This file is part of OpenTween.
+//
+// This program is free software; you can redistribute it and/or modify it
+// under the terms of the GNU General Public License as published by the Free
+// Software Foundation; either version 3 of the License, or (at your option)
+// any later version.
+//
+// This program is distributed in the hope that it will be useful, but
+// WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+// or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+// for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this program. If not, see <http://www.gnu.org/licenses/>, or write to
+// the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
+// Boston, MA 02110-1301, USA.
+
+#nullable enable
+
+using System;
+using System.Collections.Generic;
+using System.Net.Http;
+
+namespace OpenTween.Connection
+{
+    public class GetRequest : IHttpRequest
+    {
+        public required Uri RequestUri { get; set; }
+
+        public IDictionary<string, string>? Query { get; set; }
+
+        public string? EndpointName { get; set; }
+
+        public HttpRequestMessage CreateMessage(Uri baseUri)
+            => new()
+            {
+                Method = HttpMethod.Get,
+                RequestUri = BuildUriWithQuery(new(baseUri, this.RequestUri), this.Query),
+            };
+
+        public static Uri BuildUriWithQuery(Uri uri, IEnumerable<KeyValuePair<string, string>>? query)
+        {
+            if (query == null)
+                return uri;
+
+            if (!MyCommon.IsNullOrEmpty(uri.Query))
+                throw new NotSupportedException("Merging uri query is not supported");
+
+            return new Uri(uri, "?" + MyCommon.BuildQueryString(query));
+        }
+    }
+}
diff --git a/OpenTween/Connection/IApiConnection.cs b/OpenTween/Connection/IApiConnection.cs
index b7c866f4c..16e816668 100644
--- a/OpenTween/Connection/IApiConnection.cs
+++ b/OpenTween/Connection/IApiConnection.cs
@@ -1,5 +1,5 @@
 // OpenTween - Client of Twitter
-// Copyright (c) 2016 kim_upsilon (@kim_upsilon) <https://upsilo.net/~upsilon/>
+// Copyright (c) 2023 kim_upsilon (@kim_upsilon) <https://upsilo.net/~upsilon/>
 // All rights reserved.
 //
 // This file is part of OpenTween.
@@ -22,34 +22,12 @@
 #nullable enable
 
 using System;
-using System.Collections.Generic;
-using System.IO;
-using System.Linq;
-using System.Text;
 using System.Threading.Tasks;
 
 namespace OpenTween.Connection
 {
     public interface IApiConnection : IDisposable
     {
-        Task<T> GetAsync<T>(Uri uri, IDictionary<string, string>? param, string? endpointName);
-
-        Task<Stream> GetStreamAsync(Uri uri, IDictionary<string, string>? param);
-
-        Task<Stream> GetStreamAsync(Uri uri, IDictionary<string, string>? param, string? endpointName);
-
-        Task<Stream> GetStreamingStreamAsync(Uri uri, IDictionary<string, string>? param);
-
-        Task<LazyJson<T>> PostLazyAsync<T>(Uri uri, IDictionary<string, string>? param);
-
-        Task<LazyJson<T>> PostLazyAsync<T>(Uri uri, IDictionary<string, string>? param, IDictionary<string, IMediaItem>? media);
-
-        Task PostAsync(Uri uri, IDictionary<string, string>? param, IDictionary<string, IMediaItem>? media);
-
-        Task<string> PostJsonAsync(Uri uri, string json);
-
-        Task<LazyJson<T>> PostJsonAsync<T>(Uri uri, string json);
-
-        Task DeleteAsync(Uri uri);
+        Task<ApiResponse> SendAsync(IHttpRequest request);
     }
 }
diff --git a/OpenTween/Connection/IApiConnectionLegacy.cs b/OpenTween/Connection/IApiConnectionLegacy.cs
new file mode 100644
index 000000000..4175e589d
--- /dev/null
+++ b/OpenTween/Connection/IApiConnectionLegacy.cs
@@ -0,0 +1,55 @@
+// OpenTween - Client of Twitter
+// Copyright (c) 2016 kim_upsilon (@kim_upsilon) <https://upsilo.net/~upsilon/>
+// All rights reserved.
+//
+// This file is part of OpenTween.
+//
+// This program is free software; you can redistribute it and/or modify it
+// under the terms of the GNU General Public License as published by the Free
+// Software Foundation; either version 3 of the License, or (at your option)
+// any later version.
+//
+// This program is distributed in the hope that it will be useful, but
+// WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+// or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+// for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this program. If not, see <http://www.gnu.org/licenses/>, or write to
+// the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
+// Boston, MA 02110-1301, USA.
+
+#nullable enable
+
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace OpenTween.Connection
+{
+    public interface IApiConnectionLegacy : IApiConnection, IDisposable
+    {
+        Task<T> GetAsync<T>(Uri uri, IDictionary<string, string>? param, string? endpointName);
+
+        Task<Stream> GetStreamAsync(Uri uri, IDictionary<string, string>? param);
+
+        Task<Stream> GetStreamAsync(Uri uri, IDictionary<string, string>? param, string? endpointName);
+
+        Task<Stream> GetStreamingStreamAsync(Uri uri, IDictionary<string, string>? param);
+
+        Task<LazyJson<T>> PostLazyAsync<T>(Uri uri, IDictionary<string, string>? param);
+
+        Task<LazyJson<T>> PostLazyAsync<T>(Uri uri, IDictionary<string, string>? param, IDictionary<string, IMediaItem>? media);
+
+        Task PostAsync(Uri uri, IDictionary<string, string>? param, IDictionary<string, IMediaItem>? media);
+
+        Task<string> PostJsonAsync(Uri uri, string json);
+
+        Task<LazyJson<T>> PostJsonAsync<T>(Uri uri, string json);
+
+        Task DeleteAsync(Uri uri);
+    }
+}
diff --git a/OpenTween/Connection/IHttpRequest.cs b/OpenTween/Connection/IHttpRequest.cs
new file mode 100644
index 000000000..55dd9e3b4
--- /dev/null
+++ b/OpenTween/Connection/IHttpRequest.cs
@@ -0,0 +1,35 @@
+// OpenTween - Client of Twitter
+// Copyright (c) 2023 kim_upsilon (@kim_upsilon) <https://upsilo.net/~upsilon/>
+// All rights reserved.
+//
+// This file is part of OpenTween.
+//
+// This program is free software; you can redistribute it and/or modify it
+// under the terms of the GNU General Public License as published by the Free
+// Software Foundation; either version 3 of the License, or (at your option)
+// any later version.
+//
+// This program is distributed in the hope that it will be useful, but
+// WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+// or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+// for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this program. If not, see <http://www.gnu.org/licenses/>, or write to
+// the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
+// Boston, MA 02110-1301, USA.
+
+#nullable enable
+
+using System;
+using System.Net.Http;
+
+namespace OpenTween.Connection
+{
+    public interface IHttpRequest
+    {
+        string? EndpointName { get; }
+
+        HttpRequestMessage CreateMessage(Uri baseUri);
+    }
+}
diff --git a/OpenTween/Connection/TwitterApiConnection.cs b/OpenTween/Connection/TwitterApiConnection.cs
index b8bd085e1..091a32032 100644
--- a/OpenTween/Connection/TwitterApiConnection.cs
+++ b/OpenTween/Connection/TwitterApiConnection.cs
@@ -39,7 +39,7 @@
 
 namespace OpenTween.Connection
 {
-    public class TwitterApiConnection : IApiConnection, IDisposable
+    public class TwitterApiConnection : IApiConnection, IApiConnectionLegacy, IDisposable
     {
         public static Uri RestApiBase { get; set; } = new("https://api.twitter.com/1.1/");
 
@@ -98,42 +98,34 @@ private void InitializeHttpClients()
             this.HttpStreaming.Timeout = Timeout.InfiniteTimeSpan;
         }
 
-        public async Task<T> GetAsync<T>(Uri uri, IDictionary<string, string>? param, string? endpointName)
+        public async Task<ApiResponse> SendAsync(IHttpRequest request)
         {
+            var endpointName = request.EndpointName;
+
             // レートリミット規制中はAPIリクエストを送信せずに直ちにエラーを発生させる
             if (endpointName != null)
                 this.ThrowIfRateLimitExceeded(endpointName);
 
-            var requestUri = new Uri(RestApiBase, uri);
-
-            if (param != null)
-                requestUri = new Uri(requestUri, "?" + MyCommon.BuildQueryString(param));
-
-            var request = new HttpRequestMessage(HttpMethod.Get, requestUri);
+            using var requestMessage = request.CreateMessage(RestApiBase);
 
+            HttpResponseMessage? responseMessage = null;
             try
             {
-                using var response = await this.Http.SendAsync(request, HttpCompletionOption.ResponseHeadersRead)
-                    .ConfigureAwait(false);
+                responseMessage = await HandleTimeout(
+                    (token) => this.Http.SendAsync(requestMessage, HttpCompletionOption.ResponseHeadersRead, token),
+                    Networking.DefaultTimeout
+                );
 
                 if (endpointName != null)
-                    MyCommon.TwitterApiInfo.UpdateFromHeader(response.Headers, endpointName);
+                    MyCommon.TwitterApiInfo.UpdateFromHeader(responseMessage.Headers, endpointName);
 
-                await TwitterApiConnection.CheckStatusCode(response)
+                await TwitterApiConnection.CheckStatusCode(responseMessage)
                     .ConfigureAwait(false);
 
-                using var content = response.Content;
-                var responseText = await content.ReadAsStringAsync()
-                    .ConfigureAwait(false);
+                var response = new ApiResponse(responseMessage);
+                responseMessage = null; // responseMessage は ApiResponse で使用するため破棄されないようにする
 
-                try
-                {
-                    return MyCommon.CreateDataFromJson<T>(responseText);
-                }
-                catch (SerializationException ex)
-                {
-                    throw TwitterApiException.CreateFromException(ex, responseText);
-                }
+                return response;
             }
             catch (HttpRequestException ex)
             {
@@ -143,6 +135,26 @@ await TwitterApiConnection.CheckStatusCode(response)
             {
                 throw TwitterApiException.CreateFromException(ex);
             }
+            finally
+            {
+                responseMessage?.Dispose();
+            }
+        }
+
+        public async Task<T> GetAsync<T>(Uri uri, IDictionary<string, string>? param, string? endpointName)
+        {
+            var request = new GetRequest
+            {
+                RequestUri = uri,
+                Query = param,
+                EndpointName = endpointName,
+            };
+
+            using var response = await this.SendAsync(request)
+                .ConfigureAwait(false);
+
+            return await response.ReadAsJson<T>()
+                .ConfigureAwait(false);
         }
 
         /// <summary>
@@ -442,6 +454,38 @@ await TwitterApiConnection.CheckStatusCode(response)
             }
         }
 
+        public static async Task<T> HandleTimeout<T>(Func<CancellationToken, Task<T>> func, TimeSpan timeout)
+        {
+            using var cts = new CancellationTokenSource();
+            var cancellactionToken = cts.Token;
+
+            var task = Task.Run(() => func(cancellactionToken), cancellactionToken);
+            var timeoutTask = Task.Delay(timeout);
+
+            if (await Task.WhenAny(task, timeoutTask) == timeoutTask)
+            {
+                // タイムアウト
+
+                // キャンセル後のタスクで発生した例外は無視する
+                static async Task IgnoreExceptions(Task task)
+                {
+                    try
+                    {
+                        await task.ConfigureAwait(false);
+                    }
+                    catch
+                    {
+                    }
+                }
+                _ = IgnoreExceptions(task);
+                cts.Cancel();
+
+                throw new OperationCanceledException("Timeout", cancellactionToken);
+            }
+
+            return await task;
+        }
+
         protected static async Task CheckStatusCode(HttpResponseMessage response)
         {
             var statusCode = response.StatusCode;
diff --git a/OpenTween/MyCommon.cs b/OpenTween/MyCommon.cs
index 5e51960fe..e6b1f3d7c 100644
--- a/OpenTween/MyCommon.cs
+++ b/OpenTween/MyCommon.cs
@@ -719,9 +719,11 @@ public static DateTimeUtc DateTimeParse(string input)
         }
 
         public static T CreateDataFromJson<T>(string content)
+            => MyCommon.CreateDataFromJson<T>(Encoding.UTF8.GetBytes(content));
+
+        public static T CreateDataFromJson<T>(byte[] bytes)
         {
-            var buf = Encoding.Unicode.GetBytes(content);
-            using var stream = new MemoryStream(buf);
+            using var stream = new MemoryStream(bytes);
             var settings = new DataContractJsonSerializerSettings
             {
                 UseSimpleDictionaryFormat = true,
diff --git a/OpenTween/Thumbnail/Services/TonTwitterCom.cs b/OpenTween/Thumbnail/Services/TonTwitterCom.cs
index 80fe74fe3..4e55b97f6 100644
--- a/OpenTween/Thumbnail/Services/TonTwitterCom.cs
+++ b/OpenTween/Thumbnail/Services/TonTwitterCom.cs
@@ -53,8 +53,9 @@ public class TonTwitterCom : IThumbnailService
                     return null;
 
                 var largeUrl = url + ":large";
+                var apiConnection = GetApiConnection();
 
-                return new TonTwitterCom.Thumbnail
+                return new TonTwitterCom.Thumbnail(apiConnection)
                 {
                     MediaPageUrl = largeUrl,
                     ThumbnailImageUrl = url,
@@ -67,22 +68,31 @@ public class TonTwitterCom : IThumbnailService
 
         public class Thumbnail : ThumbnailInfo
         {
+            private readonly IApiConnection apiConnection;
+
+            public Thumbnail(IApiConnection apiConnection)
+                => this.apiConnection = apiConnection;
+
             public override Task<MemoryImage> LoadThumbnailImageAsync(HttpClient http, CancellationToken cancellationToken)
             {
-                return Task.Run(
-                    async () =>
+                return Task.Run(async () =>
+                {
+                    var request = new GetRequest
                     {
-                        var apiConnection = TonTwitterCom.GetApiConnection!();
+                        RequestUri = new(this.ThumbnailImageUrl),
+                    };
+
+                    using var response = await this.apiConnection.SendAsync(request)
+                        .ConfigureAwait(false);
 
-                        using var imageStream = await apiConnection.GetStreamAsync(new Uri(this.ThumbnailImageUrl), null)
-                            .ConfigureAwait(false);
+                    var imageBytes = await response.ReadAsBytes()
+                        .ConfigureAwait(false);
 
-                        cancellationToken.ThrowIfCancellationRequested();
+                    cancellationToken.ThrowIfCancellationRequested();
 
-                        return await MemoryImage.CopyFromStreamAsync(imageStream)
-                            .ConfigureAwait(false);
-                    },
-                    cancellationToken);
+                    return MemoryImage.CopyFromBytes(imageBytes);
+                },
+                cancellationToken);
             }
         }
     }