diff --git a/applications/browser-extension/package.json b/applications/browser-extension/package.json
index a906aeb705..c04bb85aa3 100644
--- a/applications/browser-extension/package.json
+++ b/applications/browser-extension/package.json
@@ -179,7 +179,6 @@
     "@playwright/test": "^1.48.2",
     "@pmmmwh/react-refresh-webpack-plugin": "^0.5.15",
     "@shopify/jest-dom-mocks": "^5.2.0",
-    "@sindresorhus/tsconfig": "^6.0.0",
     "@sinonjs/fake-timers": "^13.0.5",
     "@storybook/addon-actions": "^7.6.17",
     "@storybook/addon-essentials": "^7.6.17",
diff --git a/applications/browser-extension/tsconfig.json b/applications/browser-extension/tsconfig.json
index de1ad80454..c634f42aa1 100644
--- a/applications/browser-extension/tsconfig.json
+++ b/applications/browser-extension/tsconfig.json
@@ -1,22 +1,7 @@
 {
-  // You can see the full details at https://github.com/sindresorhus/tsconfig/blob/main/tsconfig.json
-  // Note: `strict: true` enables many flags that aren’t explicitly listed in that file
-  "extends": "@sindresorhus/tsconfig",
+  "extends": "../../tsconfig.base.json",
   "compilerOptions": {
-    "sourceMap": true,
-    "module": "esnext",
-    "target": "es2023",
-    "moduleResolution": "bundler",
-    "resolveJsonModule": true,
     "baseUrl": ".",
-    "outDir": null,
-    "declaration": false,
-
-    // TODO: Drop these lines to make TS stricter https://github.com/pixiebrix/pixiebrix-extension/issues/775
-    "strictFunctionTypes": false,
-    "noPropertyAccessFromIndexSignature": false,
-    "noImplicitReturns": false,
-    "noUnusedParameters": false,
     "paths": {
       "@/*": ["src/*"],
       "@img/*": ["img/*"],
diff --git a/libraries/utils/tsconfig.json b/libraries/utils/tsconfig.json
index 80838c478f..ee206358ed 100644
--- a/libraries/utils/tsconfig.json
+++ b/libraries/utils/tsconfig.json
@@ -1,25 +1,9 @@
 {
-  // You can see the full details at https://github.com/sindresorhus/tsconfig/blob/main/tsconfig.json
-  // Note: `strict: true` enables many flags that aren’t explicitly listed in that file
-  "extends": "@sindresorhus/tsconfig",
+  "extends": "../../tsconfig.base.json",
   "compilerOptions": {
-    "sourceMap": true,
-    "module": "esnext",
-    "target": "es2023",
-    "moduleResolution": "bundler",
-    "resolveJsonModule": true,
     "baseUrl": ".",
-    "outDir": null,
-    "declaration": false,
-
-    // TODO: Drop these lines to make TS stricter https://github.com/pixiebrix/pixiebrix-extension/issues/775
-    "strictFunctionTypes": false,
-    "noPropertyAccessFromIndexSignature": false,
-    "noImplicitReturns": false,
-    "noUnusedParameters": false,
     "paths": {
       "@/*": ["src/*"]
     }
-  },
-  "exclude": ["node_modules"]
+  }
 }
diff --git a/package.json b/package.json
index 22170d65b1..8010f2bb60 100644
--- a/package.json
+++ b/package.json
@@ -26,6 +26,7 @@
   },
   "devDependencies": {
     "knip": "^5.36.7",
-    "prettier": "3.1.0"
+    "prettier": "3.1.0",
+    "@sindresorhus/tsconfig": "^6.0.0"
   }
 }
diff --git a/pixiebrix-extension.iml b/pixiebrix-extension.iml
index aa8a3a7439..3867c8347e 100644
--- a/pixiebrix-extension.iml
+++ b/pixiebrix-extension.iml
@@ -10,6 +10,9 @@
       <excludeFolder url="file://$MODULE_DIR$/applications/browser-extension/scripts/bin" />
       <excludeFolder url="file://$MODULE_DIR$/.playwright-report" />
       <excludeFolder url="file://$MODULE_DIR$/applications/browser-extension/dist" />
+      <excludeFolder url="file://$MODULE_DIR$/applications/browser-extension/node_modules" />
+      <excludeFolder url="file://$MODULE_DIR$/libraries/utils/coverage" />
+      <excludePattern pattern="applications/browser-extension/report.html" />
     </content>
     <orderEntry type="inheritedJdk" />
     <orderEntry type="sourceFolder" forTests="false" />
diff --git a/tsconfig.base.json b/tsconfig.base.json
new file mode 100644
index 0000000000..c7f5f2a2f4
--- /dev/null
+++ b/tsconfig.base.json
@@ -0,0 +1,22 @@
+{
+  // You can see the full details at https://github.com/sindresorhus/tsconfig/blob/main/tsconfig.json
+  // Note: `strict: true` enables many flags that aren’t explicitly listed in that file
+  "extends": "@sindresorhus/tsconfig",
+  "compilerOptions": {
+    "sourceMap": true,
+    "module": "esnext",
+    "target": "es2023",
+    "moduleResolution": "bundler",
+    "resolveJsonModule": true,
+    "baseUrl": ".",
+    "outDir": null,
+    "declaration": false,
+
+    // TODO: Drop these lines to make TS stricter https://github.com/pixiebrix/pixiebrix-extension/issues/775
+    "strictFunctionTypes": false,
+    "noPropertyAccessFromIndexSignature": false,
+    "noImplicitReturns": false,
+    "noUnusedParameters": false
+  },
+  "exclude": ["node_modules"]
+}