That is not a bug, but is the consequence of canvas access being blocked when "Resist Fingerprinting" is enabled. There are more 'side effects' with using RFP like being in the UTC timezone and getting a Windows 10 user agent and getting rounded screen dimensions (see about:support).

• Mozilla/5.0 (Windows NT 10.0; rv:102.0) Gecko/20100101 Firefox/102.0

For the issue with canvas you can possibly look at this pref on the about:config page.

• about:config => privacy.resistFingerprinting.autoDeclineNoUserInputCanvasPrompts = false

• https://support.mozilla.org/en-US/kb/firefox-protection-against-fingerprinting

Thanks a bunch for the reply. Might not be a bug, but is definitely a UX problem. It should be a message when this happens so the user can know what it is happening.

Devs are thinking about it. See Users enable `privacy.resistFingerprinting` and then are surprised when it causes problems.

Hi Pedro, it's subtle but when the canvas extract is blocked, an extra permission icon should appear near the lock icon at the left end of the address bar. This is the image from the article cor-el linked, but this panel nay not drop automatically:

Some people are more attuned to strange icons appearing there than others.

Hi Pedro, it's subtle but when the canvas extract is blocked, an extra permission icon should appear near the lock icon at the left end of the address bar. This is the image from the article cor-el linked, but this panel nay not drop automatically:

Some people are more attuned to strange icons appearing there than others.

There is no warning. That is the main problem. It should be a message explaining about it.

Devs are thinking about it. See Users enable `privacy.resistFingerprinting` and then are surprised when it causes problems.

Nice! Can we comment on it??