Heavy black lines around some boxes. Version 138.0.1 Windows 10

[NancyEddy]

My Firefox just updated, and I now have heavy black frames around boxes when I hover the mouse over a tab or right-click on a page. What's the point of doing that? It's a little annoying for me. Is there a way to turn it off/on, or do I have to just deal with it?

Nancy

[siffemcon]

Try playing with the options at FF menu > General > Language and Appearance > Contrast Control.

[NancyEddy]

Didn't fix it. The rest of the page looks fine. It's just that when I right click or hover over a tab that it happens.

[siffemcon]

Does that also happen in Troubleshoot mode (https://support.mozilla.org/en-US/kb/diagnose-firefox-issues-using-troubleshoot-mode)?