chore: yjs & nextjs docs

Author: mwawrusch

Diff for: src/content/editor/getting-started/install/nextjs.mdx

@@ -72,3 +72,23 @@ export default function Home() {
 ```
 
 You should now see Tiptap in your browser. Time to give yourself a pat on the back! :)
+
+### Using yjs with Next.js
+
+To avoid the error: `Yjs was already imported. This breaks constructor checks and will lead to issues!`, add the following to your next.js config file. You might have to adjust the 'node_modules/yjs' to '../node_modules/yjs' or '../../node_modules/yjs' depending on where your node_modules are installed.
+
+```js
+const path = require('path')
+
+module.exports = {
+  webpack: (config, { isServer }) => {
+    if (!isServer) {
+      // Ensure that all imports of 'yjs' resolve to the same instance
+      config.resolve.alias['yjs'] = path.resolve(__dirname, 'node_modules/yjs')
+    }
+    return config
+  },
+}
+```
+
+The original discussion and fix can be found on [Github](https://github.com/yjs/yjs/issues/438#issuecomment-2225079409).