My granddaughter was playing with my keyboard while I had an open tab in Firefox. The image, which had been roughly 8.5" x 11", immediately shrunk to about 2"x3". There were other tabs working in the background that were not affected. Now, even after clearing cookies and browsing history, then rebooting, that particular page still opens in the shrunken state. I have no idea what combination of keys she hit or how to rectify the problem.