diff --git a/src/sql/workbench/api/browser/mainThreadNotebookDocumentsAndEditors.ts b/src/sql/workbench/api/browser/mainThreadNotebookDocumentsAndEditors.ts
index f14e84749b..fa3baaaf9d 100644
--- a/src/sql/workbench/api/browser/mainThreadNotebookDocumentsAndEditors.ts
+++ b/src/sql/workbench/api/browser/mainThreadNotebookDocumentsAndEditors.ts
@@ -574,7 +574,12 @@ export class MainThreadNotebookDocumentsAndEditors extends Disposable implements
 		addedEditors.forEach(editor => {
 			let modelUrl = editor.uri;
 			const store = new DisposableStore();
-			store.add(editor.contentChanged((e) => this._proxy.$acceptModelChanged(modelUrl, this._toNotebookChangeData(e, editor))));
+			store.add(editor.contentChanged((e) => {
+				// Cell source updates are handled by vscode editor updates in main/extHost Documents
+				if (e.changeType !== NotebookChangeType.CellSourceUpdated) {
+					this._proxy.$acceptModelChanged(modelUrl, this._toNotebookChangeData(e, editor));
+				}
+			}));
 			this._modelToDisposeMap.set(editor.uri.toString(), store);
 		});
 	}