diff --git a/test/api/MouseTracking.api.ts b/test/api/MouseTracking.api.ts
index 602d630c..1372b567 100644
--- a/test/api/MouseTracking.api.ts
+++ b/test/api/MouseTracking.api.ts
@@ -11,8 +11,10 @@ const APP = 'http://127.0.0.1:3000/test';
 
 let browser: puppeteer.Browser;
 let page: puppeteer.Page;
-const width = 1024;
-const height = 768;
+// adjusted to work inside devcontainer
+// see https://github.com/xtermjs/xterm.js/issues/2379
+const width = 1280;
+const height = 960;
 
 // adjust terminal row/col size so we can test
 // >80 up to 223 and >255