Over 3 years later on a new MacBook with a new Firefox installation the same error appears again. Also on this device it worked without any problems for about a year. Last week the "old" bug came back and it stays since then: When I open the Firefox extension for Enpass, the dropdown UI is broken (scaled down to 25% of the size leaving a red rectangle, UI elements seems to be rearranged/broken and it's unusable - doesn't respond to mouse clicks etc.). See attached screenshot.
I restarted Firefox and the whole MacBook, I reinstalled the extension, nothing seems to help.
I'm surprised that I'm almost the only one with this problem. Very weird that it happened already on three different MacBooks now. Maybe it's connected to one of my other Firefox extensions that I've used in each setup (see 2nd screenshot).
Setup: MacBook Pro Mid'15, macOS 12.6.8, Firefox 118.0.1, Enpass 6.9.1 (1512), Enpass FF extension 6.8.8