diff --git a/src/vs/workbench/parts/extensions/electron-browser/extensionsViews.ts b/src/vs/workbench/parts/extensions/electron-browser/extensionsViews.ts
index 3c7d35378b0..df49559b538 100644
--- a/src/vs/workbench/parts/extensions/electron-browser/extensionsViews.ts
+++ b/src/vs/workbench/parts/extensions/electron-browser/extensionsViews.ts
@@ -234,7 +234,7 @@ export class ExtensionsListView extends ViewsViewletPanel {
 				const languageTag = languageName ? ` tag:"${languageName}"` : '';
 
 				// Construct a rich query
-				return `tag:"__ext_${ext}" ${keywords.map(tag => `tag:"${tag}"`).join(' ')}${languageTag}`;
+				return `tag:"__ext_.${ext}" ${keywords.map(tag => `tag:"${tag}"`).join(' ')}${languageTag}`;
 			});
 
 			if (names.length) {