Thanks for the report, but I can not recreate the issue. All works fine in my tests - even with Adblock Plus installed. If you use NoScript, you need to allow Javascript to run on the page, otherwise Copyfish can not calculate the height of the screenshot. But this would result in a different "image too large" error, so I assume you allowed this already.

Can you please send a screenshot of the situation to copyfish@a9t9.com ? This might us an idea on how to recreate the problem.

You might also want to try "Copyfish for Chrome" and see if this one works better for you. This will be useful information as well. Thanks!