diff --git a/src/vs/workbench/services/extensions/browser/webWorkerExtensionHost.ts b/src/vs/workbench/services/extensions/browser/webWorkerExtensionHost.ts
index 23724c11474..f0f7cb8f676 100644
--- a/src/vs/workbench/services/extensions/browser/webWorkerExtensionHost.ts
+++ b/src/vs/workbench/services/extensions/browser/webWorkerExtensionHost.ts
@@ -16,6 +16,7 @@ import { ILabelService } from 'vs/platform/label/common/label';
 import { ILogService } from 'vs/platform/log/common/log';
 import { IExtensionDescription } from 'vs/platform/extensions/common/extensions';
 import * as platform from 'vs/base/common/platform';
+import * as browser from 'vs/base/browser/browser';
 import * as dom from 'vs/base/browser/dom';
 import { URI } from 'vs/base/common/uri';
 import { IExtensionHost, ExtensionHostLogFileName, ExtensionHostKind } from 'vs/workbench/services/extensions/common/extensions';
@@ -82,7 +83,7 @@ export class WebWorkerExtensionHost extends Disposable implements IExtensionHost
 
 	public async start(): Promise<IMessagePassingProtocol> {
 		if (!this._protocolPromise) {
-			if (platform.isWeb && this._wrapInIframe()) {
+			if (platform.isWeb && !browser.isSafari && this._wrapInIframe()) {
 				this._protocolPromise = this._startInsideIframe();
 			} else {
 				this._protocolPromise = this._startOutsideIframe();