diff --git a/client/package.json b/client/package.json
index 9c8f2ac86ad8..9b4021e45a05 100644
--- a/client/package.json
+++ b/client/package.json
@@ -54,7 +54,7 @@
       "node"
     ],
     "moduleNameMapper": {
-      "^.+\\.module\\.(css|sass|scss)$": "identity-obj-proxy"
+      "\\.s?css(\\?css)?$": "<rootDir>/config/jest/cssTransform.js"
     },
     "modulePaths": [],
     "resetMocks": true,
@@ -78,8 +78,7 @@
       "^(?!.*\\.(js|jsx|mjs|cjs|ts|tsx|css|json)$)": "<rootDir>/config/jest/fileTransform.js"
     },
     "transformIgnorePatterns": [
-      "/node_modules/(?!@mozilla/glean/.*)/",
-      "^.+\\.module\\.(css|sass|scss)$"
+      "/node_modules/(?!@mozilla/glean/.*)/"
     ],
     "watchPlugins": [
       "jest-watch-typeahead/filename",
diff --git a/package.json b/package.json
index fdc929918a91..eb355b20a042 100644
--- a/package.json
+++ b/package.json
@@ -224,7 +224,6 @@
     "html-validate": "^8.28.0",
     "html-webpack-plugin": "^5.6.3",
     "husky": "^9.1.7",
-    "identity-obj-proxy": "^3.0.0",
     "ignore-loader": "^0.1.2",
     "jest": "^29.7.0",
     "jest-environment-jsdom": "^29.7.0",
diff --git a/yarn.lock b/yarn.lock
index a33b5551b38c..8505b8bd70e2 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -8065,11 +8065,6 @@ hard-rejection@^2.1.0:
   resolved "https://registry.yarnpkg.com/hard-rejection/-/hard-rejection-2.1.0.tgz#1c6eda5c1685c63942766d79bb40ae773cecd883"
   integrity sha512-VIZB+ibDhx7ObhAe7OVtoEbuP4h/MuOTHJ+J8h/eBXotJYl0fBgR72xDFCKgIh22OJZIOVNxBMWuhAr10r8HdA==
 
-harmony-reflect@^1.4.6:
-  version "1.6.2"
-  resolved "https://registry.yarnpkg.com/harmony-reflect/-/harmony-reflect-1.6.2.tgz#31ecbd32e648a34d030d86adb67d4d47547fe710"
-  integrity sha512-HIp/n38R9kQjDEziXyDTuW3vvoxxyxjxFzXLrBr18uB47GnSt+G9D29fqrpM5ZkspMcPICud3XsBJQ4Y2URg8g==
-
 has-bigints@^1.0.1, has-bigints@^1.0.2:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/has-bigints/-/has-bigints-1.0.2.tgz#0871bd3e3d51626f6ca0966668ba35d5602d6eaa"
@@ -8660,13 +8655,6 @@ identifier-regex@^1.0.0:
   dependencies:
     reserved-identifiers "^1.0.0"
 
-identity-obj-proxy@^3.0.0:
-  version "3.0.0"
-  resolved "https://registry.yarnpkg.com/identity-obj-proxy/-/identity-obj-proxy-3.0.0.tgz#94d2bda96084453ef36fbc5aaec37e0f79f1fc14"
-  integrity sha512-00n6YnVHKrinT9t0d9+5yZC6UBNJANpYEQvL2LlX6Ab9lnmxzIRcEmTPuyGScvl1+jKuCICX1Z0Ab1pPKKdikA==
-  dependencies:
-    harmony-reflect "^1.4.6"
-
 ieee754@^1.1.13, ieee754@^1.2.1:
   version "1.2.1"
   resolved "https://registry.yarnpkg.com/ieee754/-/ieee754-1.2.1.tgz#8eb7a10a63fff25d15a57b001586d177d1b0d352"