diff --git a/src/vs/platform/remote/common/tunnel.ts b/src/vs/platform/remote/common/tunnel.ts
index 9fdba618115..d8d8c6c5751 100644
--- a/src/vs/platform/remote/common/tunnel.ts
+++ b/src/vs/platform/remote/common/tunnel.ts
@@ -4,6 +4,7 @@
  *--------------------------------------------------------------------------------------------*/
 
 import { createDecorator } from 'vs/platform/instantiation/common/instantiation';
+import { URI } from 'vs/base/common/uri';
 
 export const ITunnelService = createDecorator<ITunnelService>('tunnelService');
 
@@ -19,3 +20,17 @@ export interface ITunnelService {
 
 	openTunnel(remotePort: number): Promise<RemoteTunnel> | undefined;
 }
+
+export function extractLocalHostUriMetaDataForPortMapping(uri: URI): { address: string, port: number } | undefined {
+	if (uri.scheme !== 'http' && uri.scheme !== 'https') {
+		return undefined;
+	}
+	const localhostMatch = /^(localhost|127\.0\.0\.1):(\d+)$/.exec(uri.authority);
+	if (!localhostMatch) {
+		return undefined;
+	}
+	return {
+		address: localhostMatch[1],
+		port: +localhostMatch[2],
+	};
+}
diff --git a/src/vs/workbench/api/browser/mainThreadWindow.ts b/src/vs/workbench/api/browser/mainThreadWindow.ts
index 264d788c6c9..1bedb369aa6 100644
--- a/src/vs/workbench/api/browser/mainThreadWindow.ts
+++ b/src/vs/workbench/api/browser/mainThreadWindow.ts
@@ -9,9 +9,8 @@ import { URI, UriComponents } from 'vs/base/common/uri';
 import { IWindowService } from 'vs/platform/windows/common/windows';
 import { extHostNamedCustomer } from 'vs/workbench/api/common/extHostCustomers';
 import { ExtHostContext, ExtHostWindowShape, IExtHostContext, MainContext, MainThreadWindowShape, IOpenUriOptions } from '../common/extHost.protocol';
-import { ITunnelService, RemoteTunnel } from 'vs/platform/remote/common/tunnel';
+import { ITunnelService, RemoteTunnel, extractLocalHostUriMetaDataForPortMapping } from 'vs/platform/remote/common/tunnel';
 import { IWorkbenchEnvironmentService } from 'vs/workbench/services/environment/common/environmentService';
-import { extractLocalHostUriMetaDataForPortMapping } from 'vs/workbench/contrib/webview/common/portMapping';
 import { IOpenerService } from 'vs/platform/opener/common/opener';
 
 @extHostNamedCustomer(MainContext.MainThreadWindow)
diff --git a/src/vs/workbench/contrib/webview/common/portMapping.ts b/src/vs/workbench/contrib/webview/common/portMapping.ts
index e47390dcf05..30041eb213b 100644
--- a/src/vs/workbench/contrib/webview/common/portMapping.ts
+++ b/src/vs/workbench/contrib/webview/common/portMapping.ts
@@ -7,21 +7,7 @@ import { Disposable } from 'vs/base/common/lifecycle';
 import { URI } from 'vs/base/common/uri';
 import * as modes from 'vs/editor/common/modes';
 import { REMOTE_HOST_SCHEME } from 'vs/platform/remote/common/remoteHosts';
-import { ITunnelService, RemoteTunnel } from 'vs/platform/remote/common/tunnel';
-
-export function extractLocalHostUriMetaDataForPortMapping(uri: URI): { address: string, port: number } | undefined {
-	if (uri.scheme !== 'http' && uri.scheme !== 'https') {
-		return undefined;
-	}
-	const localhostMatch = /^(localhost|127\.0\.0\.1):(\d+)$/.exec(uri.authority);
-	if (!localhostMatch) {
-		return undefined;
-	}
-	return {
-		address: localhostMatch[1],
-		port: +localhostMatch[2],
-	};
-}
+import { ITunnelService, RemoteTunnel, extractLocalHostUriMetaDataForPortMapping } from 'vs/platform/remote/common/tunnel';
 
 export class WebviewPortMappingManager extends Disposable {