‘Canvas image extraction prompt’ displays useless message
+canvas.siteprompt=This website (%S) attempted to access image data on a canvas. Blank (white) image data was returned this time.
Why should I care? (OK, I know this is a fingerprinting risk, but please explain that to the user you just popped up a message box at.)
To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information