Suppress CodeMirror DOM position errors for offscreen editors

src/client/main.jsx

@@ -3,6 +3,28 @@ import * as ReactDOM from 'react-dom/client';
 import App from './App';
 import { BrowserRouter } from 'react-router-dom';
 
+// Global error handler to catch CodeMirror DOM position errors
+// These can occur when CodeMirror instances are created but not yet
+// attached to the DOM, or when presence indicators try to render
+// on offscreen editor instances.
+window.addEventListener('error', (event) => {
+  // Check if this is the specific CodeMirror posFromDOM/posAtDOM error
+  if (
+    event.error instanceof RangeError &&
+    event.error.message.includes(
+      'Trying to find position for a DOM position outside of the document',
+    )
+  ) {
+    // Log the error for debugging purposes
+    console.log(
+      'Suppressed CodeMirror DOM position error:',
+      event.error,
+    );
+    // Prevent the error from being logged to console by returning true
+    return true;
+  }
+});
+
 ReactDOM.createRoot(document.getElementById('root')).render(
   <BrowserRouter>
     <App />