Make shell nicer

data/shell.html

@@ -33,15 +33,9 @@
       const text = String(message || 'Unknown error');
       console.error(text);
       errorBox.style.display = 'block';
-      errorBox.textContent = text + '\n\n(click to dismiss)';
+      errorBox.textContent = text;
     }
 
-    errorBox.addEventListener('click', () => {
-      errorBox.style.display = 'none';
-      errorBox.textContent = '';
-      Module.canvas.focus();
-    });
-
     window.addEventListener('error', (event) => {
       showError(event.error && event.error.stack ? event.error.stack : event.message);
     });