diff --git a/packages/plugin-ext/src/main/browser/uri-main.ts b/packages/plugin-ext/src/main/browser/uri-main.ts
index 14bb9fc77d5de..6e18cdea5241c 100644
--- a/packages/plugin-ext/src/main/browser/uri-main.ts
+++ b/packages/plugin-ext/src/main/browser/uri-main.ts
@@ -36,7 +36,7 @@ export class UriMainImpl implements UriMain, Disposable {
 
         this.openHandler = {
             id: 'theia-plugin-open-handler',
-            canHandle: async (uri: URI, options?: OpenerOptions | undefined): Promise<number>  => {
+            canHandle: async (uri: URI, options?: OpenerOptions | undefined): Promise<number> => {
                 if (uri.scheme !== FrontendApplicationConfigProvider.get().electron.uriScheme) {
                     return 0;
                 }
@@ -48,7 +48,7 @@ export class UriMainImpl implements UriMain, Disposable {
             },
             open: async (uri: URI, options?: OpenerOptions | undefined): Promise<undefined> => {
                 if (!this.handlers.has(uri.authority)) {
-
+                    throw new Error(`No plugin to handle this uri: : '${uri}'`);
                 }
                 this.proxy.$handleExternalUri(uri.toComponents());
             }
@@ -66,7 +66,7 @@ export class UriMainImpl implements UriMain, Disposable {
         this.handlers.add(pluginId);
     }
 
-    async $unregisterUriHandler(pluginId: string):  Promise<void> {
+    async $unregisterUriHandler(pluginId: string): Promise<void> {
         this.handlers.delete(pluginId);
     }
 }