div class="watermark__overlay" style="position: fixed; inset: 0px; background: rgba(0, 0, 0, 0) url("data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAQCAYAAAAf8/9hAAAAFklEQVQ4jWP4TyFgGDVg1IBRA4aLAQBdePwusY1T3AAAAABJRU5ErkJggg==") repeat scroll 0% 0%; z-index: 5000; pointer-events: none;"

You are getting a solid white background image while I'm getting a transparent image. I don't know why that would be.

your base64 data is different than mine

CapSel said

your base64 data is different than mine

Yes, I can't explain it. A script injects that element into the page, but it is "minified" so it's extremely hard to follow.

List of my addons: - Cookie AutoDelete - Enhencer for Youtube - floccus - LessPass - Privacy Badger - uBlock Origin all disabled.

Default theme.

Just in case it helps someone.

I removed all addons by hand - still the image is not transparent. I'll try to check what flags in "about:config" are not default and tweak them...

Found it: privacy.resistFingerprinting=true and the page is white privacy.resistFingerprinting=false and the page works

So... In theory I can set up uBlock to block divs with this class but it would be just temporary solution. There must be some bug in firefox that causes this. ... in my not so humble opinion ;)

The "resist fingerprinting" feature may be trying to make sure you are aware of elements that are transparent. Definitely not helpful on this page because unlike a small tracking area, it covers the entire screen. Better to remove that element than see it, but it's probably difficult to program that in advance/globally.

Do you want to file a bug?

https://bugzilla.mozilla.org/

Note: resist fingerprinting disguises your true Firefox version, so in the bug, make sure to mention what that is.

Yes, I'm going to file a bug. I haven't found any bug that describes my situation or I missed it - there are plenty of them about "privacy fingerprinting".

Here it is: https://bugzilla.mozilla.org/show_bug.cgi?id=1540308

If canvas is used then this might be part of the problem.

Good work both of you.