Right-click menu is completely blank.
This has been a bug for a long time but devs have never reproduced and don't know what causes it.
https://bugzilla.mozilla.org/show_bug.cgi?id=2034677
Users report that it fixes after some kind of restart. You can try, in order:
- Restarting the browser.
- Restarting the browser in "troubleshoot mode" then restarting it again into normal mode.
- Restarting the whole computer.