Canvas permission popup steals focus from textfield

When navigating to a site (for example a login form), I start filling in the form, and suddenly the popup appears and my keystrokes are not registered anymore.

Can we maybe just set privacy.resistFingerprinting.autoDeclineNoUserInputCanvasPrompts to true?

There's many threads on forums, reddit & stack exchange of users being annoyed by the popup.

Trac:
Username: jikin