If Marvin is crashing or otherwise behaving strangely, we might ask you to check for errors in your browser's console so that we can figure out what's going on.
Chrome / Opera / Safari / Firefox
First, right click the page and click "Inspect" or "Inspect Element":
Next, find the "Console" tab. You may have to click the » symbol to find it:
Look for a red error message and send us a screenshot or copy and paste the text. Be sure to click the ▶ symbol to expand the error message!
In Internet Explorer, press F12 on your keyboard to open the developer tools, then click the Console tab. You may need to reload the web page with the console open in order to see any errors.