Attached: 2 images Since I’m the idiot learning this by filing bug reports, I thought I’d pass it on to all other #FireFox users on here. If you enable resistFingerprinting in about:config, the web site will start showing you weird stripy graphics anywhere an HTML5 canvas graphic would be generated. To fix this for sites you trust is to click on the tiny graphic icon to the left of the URL and allow use of your HTML5 canvas. Big thanks to the patient Bugzilla guys for dealing with my bug report and the solution.