uiwjs/react-codemirror v4.0.0-rc.4

on GitHub

import CodeMirror from '@uiw/react-codemirror';
- import 'codemirror/mode/javascript/javascript';
+ import { javascript } from "@codemirror/lang-javascript";

const code = 'console.log("hello world!");';

<CodeMirror
  value={code}
-  options={{
-    mode: 'js',
-  }}
+  extensions={[
+    javascript({ jsx: true })
+  ]}
/>