diff --git a/toolkit/content/Troubleshoot.jsm b/toolkit/content/Troubleshoot.jsm
index 1dd4993bff5b..83e5a5d67683 100644
--- a/toolkit/content/Troubleshoot.jsm
+++ b/toolkit/content/Troubleshoot.jsm
@@ -295,6 +295,8 @@ let dataProviders = {
       .parseFromString("<html/>", "text/html");
 
     let canvas = doc.createElement("canvas");
+    canvas.width = 1;
+    canvas.height = 1;
 
     let gl;
     try {