diff --git a/src/vs/workbench/api/browser/mainThreadWindow.ts b/src/vs/workbench/api/browser/mainThreadWindow.ts
index bbce19a33881d1e988547374c8598d2706243f36..2a431111e936dd220d71aba93f416da363062205 100644
--- a/src/vs/workbench/api/browser/mainThreadWindow.ts
+++ b/src/vs/workbench/api/browser/mainThreadWindow.ts
@@ -42,9 +42,17 @@ export class MainThreadWindow implements MainThreadWindowShape {
 		return Promise.resolve(this.hostService.hasFocus);
 	}
 
-	async $openUri(uriComponents: UriComponents, options: IOpenUriOptions): Promise<boolean> {
+	async $openUri(uriComponents: UriComponents, uriString: string | undefined, options: IOpenUriOptions): Promise<boolean> {
 		const uri = URI.from(uriComponents);
-		return this.openerService.open(uri, { openExternal: true, allowTunneling: options.allowTunneling });
+		let target: URI | string;
+		if (uriString && URI.parse(uriString).toString() === uri.toString()) {
+			// called with string and no transformation happened -> keep string
+			target = uriString;
+		} else {
+			// called with URI or transformed -> use uri
+			target = uri;
+		}
+		return this.openerService.open(target, { openExternal: true, allowTunneling: options.allowTunneling });
 	}
 
 	async $asExternalUri(uriComponents: UriComponents, options: IOpenUriOptions): Promise<UriComponents> {
diff --git a/src/vs/workbench/api/common/extHost.protocol.ts b/src/vs/workbench/api/common/extHost.protocol.ts
index 9bc433a17277d39e3e6740ed79a92b96c48abe7a..5df456ab6c7e1283d91a193315da3d95c2c8d4bb 100644
--- a/src/vs/workbench/api/common/extHost.protocol.ts
+++ b/src/vs/workbench/api/common/extHost.protocol.ts
@@ -759,7 +759,7 @@ export interface IOpenUriOptions {
 
 export interface MainThreadWindowShape extends IDisposable {
 	$getWindowVisibility(): Promise<boolean>;
-	$openUri(uri: UriComponents, options: IOpenUriOptions): Promise<boolean>;
+	$openUri(uri: UriComponents, uriString: string | undefined, options: IOpenUriOptions): Promise<boolean>;
 	$asExternalUri(uri: UriComponents, options: IOpenUriOptions): Promise<UriComponents>;
 }
 
diff --git a/src/vs/workbench/api/common/extHostRequireInterceptor.ts b/src/vs/workbench/api/common/extHostRequireInterceptor.ts
index b6f94048fbd3ba43c675e37a8d99adb392b1380f..c06e86c83051c9a92fe0ba7cb34fc0be71fbe3fa 100644
--- a/src/vs/workbench/api/common/extHostRequireInterceptor.ts
+++ b/src/vs/workbench/api/common/extHostRequireInterceptor.ts
@@ -245,9 +245,9 @@ class OpenNodeModuleFactory implements INodeModuleFactory {
 				return this.callOriginal(target, options);
 			}
 			if (uri.scheme === 'http' || uri.scheme === 'https') {
-				return mainThreadWindow.$openUri(uri, { allowTunneling: true });
+				return mainThreadWindow.$openUri(uri, target, { allowTunneling: true });
 			} else if (uri.scheme === 'mailto' || uri.scheme === this._appUriScheme) {
-				return mainThreadWindow.$openUri(uri, {});
+				return mainThreadWindow.$openUri(uri, target, {});
 			}
 			return this.callOriginal(target, options);
 		};
diff --git a/src/vs/workbench/api/common/extHostWindow.ts b/src/vs/workbench/api/common/extHostWindow.ts
index 8ce82ac8b2dcba730ab9c3ae5a9f157bba766501..f8c5d5fa3d782a018917539287c9ef0dc0c4bb4a 100644
--- a/src/vs/workbench/api/common/extHostWindow.ts
+++ b/src/vs/workbench/api/common/extHostWindow.ts
@@ -39,7 +39,9 @@ export class ExtHostWindow implements ExtHostWindowShape {
 	}
 
 	openUri(stringOrUri: string | URI, options: IOpenUriOptions): Promise<boolean> {
+		let uriAsString: string | undefined;
 		if (typeof stringOrUri === 'string') {
+			uriAsString = stringOrUri;
 			try {
 				stringOrUri = URI.parse(stringOrUri);
 			} catch (e) {
@@ -51,7 +53,7 @@ export class ExtHostWindow implements ExtHostWindowShape {
 		} else if (stringOrUri.scheme === Schemas.command) {
 			return Promise.reject(`Invalid scheme '${stringOrUri.scheme}'`);
 		}
-		return this._proxy.$openUri(stringOrUri, options);
+		return this._proxy.$openUri(stringOrUri, uriAsString, options);
 	}
 
 	async asExternalUri(uri: URI, options: IOpenUriOptions): Promise<URI> {