diff --git a/.eslintrc.js b/.eslintrc.js
index 5a4bfa44890..59061092781 100644
--- a/.eslintrc.js
+++ b/.eslintrc.js
@@ -157,6 +157,8 @@ module.exports = {
         'rulesdir/prettier-comments': 'error',
         // Enforces clean up of used resources.
         'rulesdir/use-using': 'error',
+        // Enforces consistent file extension
+        'rulesdir/extensions': 'error',
         // Brackets keep code readable.
         curly: ['error', 'all'],
         // Brackets keep code readable and `return` intentions clear.
diff --git a/packages/puppeteer-core/src/bidi/lifecycle.ts b/packages/puppeteer-core/src/bidi/lifecycle.ts
index 5bb52b08e7f..1d0b44fb3b3 100644
--- a/packages/puppeteer-core/src/bidi/lifecycle.ts
+++ b/packages/puppeteer-core/src/bidi/lifecycle.ts
@@ -19,10 +19,10 @@ import type {
   ObservableInput,
   ObservedValueOf,
   OperatorFunction,
-} from '../../third_party/rxjs/rxjs';
-import {catchError} from '../../third_party/rxjs/rxjs';
-import type {PuppeteerLifeCycleEvent} from '../cdp/LifecycleWatcher';
-import {ProtocolError, TimeoutError} from '../common/Errors';
+} from '../../third_party/rxjs/rxjs.js';
+import {catchError} from '../../third_party/rxjs/rxjs.js';
+import type {PuppeteerLifeCycleEvent} from '../cdp/LifecycleWatcher.js';
+import {ProtocolError, TimeoutError} from '../common/Errors.js';
 
 export type BiDiNetworkIdle = Extract<
   PuppeteerLifeCycleEvent,
diff --git a/packages/puppeteer-core/tools/ensure-correct-devtools-protocol-package.ts b/packages/puppeteer-core/tools/ensure-correct-devtools-protocol-package.ts
index fcc35e1cb5f..6f17bf71cb4 100644
--- a/packages/puppeteer-core/tools/ensure-correct-devtools-protocol-package.ts
+++ b/packages/puppeteer-core/tools/ensure-correct-devtools-protocol-package.ts
@@ -33,7 +33,6 @@
  * find the one closest to our Chrome revision.
  */
 
-// eslint-disable-next-line import/extensions
 import {execSync} from 'child_process';
 
 import packageJson from '../package.json' assert {type: 'json'};
diff --git a/tools/eslint/src/extensions.ts b/tools/eslint/src/extensions.ts
new file mode 100644
index 00000000000..68f236983f3
--- /dev/null
+++ b/tools/eslint/src/extensions.ts
@@ -0,0 +1,58 @@
+/**
+ * Copyright 2023 Google Inc. All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import {ESLintUtils} from '@typescript-eslint/utils';
+
+const createRule = ESLintUtils.RuleCreator(name => {
+  return `https://github.com/puppeteer/puppeteer/tree/main/tools/eslint/${name}.js`;
+});
+
+const enforceExtensionRule = createRule<[], 'extensionsRule'>({
+  name: 'extensions',
+  meta: {
+    docs: {
+      description: 'Requires `.js` for imports',
+      requiresTypeChecking: false,
+    },
+    messages: {
+      extensionsRule: 'Add `.js` to import.',
+    },
+    schema: [],
+    fixable: 'code',
+    type: 'problem',
+  },
+  defaultOptions: [],
+  create(context) {
+    return {
+      ImportDeclaration(node): void {
+        const file = node.source.value.split('/').pop();
+
+        if (!node.source.value.startsWith('.') || file?.includes('.')) {
+          return;
+        }
+        context.report({
+          node: node.source,
+          messageId: 'extensionsRule',
+          fix(fixer) {
+            return fixer.replaceText(node.source, `'${node.source.value}.js'`);
+          },
+        });
+      },
+    };
+  },
+});
+
+export = enforceExtensionRule;