Update a few more mentions to the main channel (#11173)

In response to
#11172 (comment)

src/content/release/archive-whats-new.md

@@ -48,7 +48,7 @@ You might also check out the [Dart 3.3 release][] blog post.
   [Flutter and Dart 2024 Roadmap][].
 * Check out [Harness the Gemini API in your Dart and Flutter apps][].
 
-[Flutter and Dart 2024 Roadmap]: {{site.github}}/flutter/flutter/blob/master/docs/roadmap/Roadmap.md
+[Flutter and Dart 2024 Roadmap]: {{site.github}}/flutter/flutter/blob/main/docs/roadmap/Roadmap.md
 [Harness the Gemini API in your Dart and Flutter apps]: {{site.flutter-medium}}/harness-the-gemini-api-in-your-dart-and-flutter-apps-00573e560381
 
 ## 15 November 2023: 3.16 release
@@ -1206,7 +1206,7 @@ Docs added and updated since the last announcement include:
 * A new [implicit animations][] codelab is available
   featuring DartPad.
   (To run it, you don't need to download any software!)
-* Alpha support for MacOS (desktop) is now available in
+* Alpha support for macOS (desktop) is now available in
   release 1.13 on the master and dev channels.
   For more information, see [Desktop support for Flutter][].
 * The iOS section of the [app size][] page is updated to reflect

src/content/release/archive.md

@@ -1,7 +1,7 @@
 ---
 title: Flutter SDK archive
 short-title: Archive
-description: "All current Flutter SDK releases: stable, beta, and master."
+description: "All current Flutter SDK releases: stable, beta, and main."
 toc: false
 ---
 
@@ -55,22 +55,25 @@ curl [provenance URL] | jq -r .payload | base64 -d | jq
 {% endtab %}
 {% endtabs %}
 
-## Master channel
+<a id="master-channel" aria-hidden="true"></a>
 
-Installation bundles are not available for master.
+## Main channel
+
+Installation bundles are not available for the `main` channel
+(which was previously known as the `master` channel).
 However, you can get the SDK directly from
-[GitHub repo][] by cloning the master channel,
+[GitHub repo][] by cloning the main channel,
 and then triggering a download of the SDK dependencies:
 
 ```console
-$ git clone -b master https://github.com/flutter/flutter.git
+$ git clone -b main https://github.com/flutter/flutter.git
 $ ./flutter/bin/flutter --version
 ```
 
 For additional details on how our installation bundles are structured,
 see [Installation bundles][].
 
-[Flutter's channels]: {{site.repo.flutter}}/blob/master/docs/releases/Flutter-build-release-channels.md
+[Flutter's channels]: {{site.repo.flutter}}/blob/main/docs/releases/Flutter-build-release-channels.md
 [release notes]: /release/release-notes
 [GitHub repo]: {{site.repo.flutter}}
-[Installation bundles]: {{site.repo.flutter}}/blob/master/docs/infra/Flutter-Installation-Bundles.md
+[Installation bundles]: {{site.repo.flutter}}/blob/main/docs/infra/Flutter-Installation-Bundles.md

src/content/release/upgrade.md

@@ -71,7 +71,7 @@ it is updated to the latest **beta** release.
 
 ### Other channels
 
-We currently have one other channel, **master**.
+We currently have one other channel, **main** (previously known as **master**).
 People who [contribute to Flutter][] use this channel.
 
 This channel is not as thoroughly tested as
@@ -80,7 +80,7 @@ the **beta** and **stable** channels.
 We do not recommend using this channel as
 it is more likely to contain serious regressions.
 
-The latest documentation for the **master** branch
+The latest documentation for the **main** branch
 is at: <https://main-api.flutter.dev>
 
 ### Changing channels