diff --git a/src/vs/workbench/api/common/extHost.api.impl.ts b/src/vs/workbench/api/common/extHost.api.impl.ts
index 3b658592ed8..865ded63659 100644
--- a/src/vs/workbench/api/common/extHost.api.impl.ts
+++ b/src/vs/workbench/api/common/extHost.api.impl.ts
@@ -1257,10 +1257,6 @@ export function createApiFactoryAndRegisterActors(accessor: ServicesAccessor): I
 				// checkProposedApiEnabled(extension);
 				return extHostTypes.CellKind;
 			},
-			get CellOutputKind() {
-				// checkProposedApiEnabled(extension);
-				return extHostTypes.CellOutputKind;
-			},
 			get NotebookCellRunState() {
 				// checkProposedApiEnabled(extension);
 				return extHostTypes.NotebookCellRunState;
diff --git a/src/vs/workbench/api/common/extHostTypes.ts b/src/vs/workbench/api/common/extHostTypes.ts
index 45c8dfe60de..96072d5c471 100644
--- a/src/vs/workbench/api/common/extHostTypes.ts
+++ b/src/vs/workbench/api/common/extHostTypes.ts
@@ -2890,46 +2890,10 @@ export class NotebookCellOutputItem {
 }
 
 export class NotebookCellOutput {
-
-	// static _toOld(output: IOutputDto): vscode.CellOutput {
-	// 	if (output.data['application/x.notebook.stream']) {
-	// 		return {
-	// 			outputKind: CellOutputKind.Text,
-	// 			text: output.data['application/x.notebook.stream'] as string
-	// 		};
-	// 	} else if (output.data['application/x.notebook.error-traceback']) {
-	// 		return {
-	// 			outputKind: CellOutputKind.Error,
-	// 			ename: (output.data['application/x.notebook.error-traceback'] as any)['ename'],
-	// 			evalue: (output.data['application/x.notebook.error-traceback'] as any)['evalue'],
-	// 			traceback: (output.data['application/x.notebook.error-traceback'] as any)['traceback'],
-	// 		};
-	// 	} else {
-	// 		return {
-	// 			outputKind: CellOutputKind.Rich,
-	// 			data: output.data,
-	// 			metadata: output.metadata
-	// 		};
-	// 	}
-	// }
-
-	// static _fromOld(output: vscode.CellOutput, id?: string): NotebookCellOutput {
-	// 	switch (output.outputKind) {
-	// 		case CellOutputKind.Error:
-	// 			return new NotebookCellOutput([new NotebookCellOutputItem('application/x.notebook.error-traceback', output)]);
-	// 		case CellOutputKind.Text:
-	// 			return new NotebookCellOutput([new NotebookCellOutputItem('application/x.notebook.stream', output.text)]);
-	// 		case CellOutputKind.Rich:
-	// 			const items: NotebookCellOutputItem[] = [];
-	// 			for (const key in output.data) {
-	// 				items.push(new NotebookCellOutputItem(key, output.data[key], output.metadata?.custom ? output.metadata?.custom[key] : undefined));
-	// 			}
-	// 			return new NotebookCellOutput(items, id);
-	// 	}
-	// 	throw new Error('invalid outputKind');
-	// }
-
-	constructor(readonly outputs: NotebookCellOutputItem[], readonly id: string = generateUuid()) { }
+	constructor(
+		readonly outputs: NotebookCellOutputItem[],
+		readonly id: string = generateUuid()
+	) { }
 }
 
 export enum CellKind {
@@ -2937,12 +2901,6 @@ export enum CellKind {
 	Code = 2
 }
 
-export enum CellOutputKind {
-	Text = 1,
-	Error = 2,
-	Rich = 3
-}
-
 export enum NotebookCellRunState {
 	Running = 1,
 	Idle = 2,