How would I stop the close tab X from highlighting when I hover my cursor over it?
I have managed to hide the "x" (close tab button) with this:
/*** Hide Tab Close buttons ***/ .tabbrowser-tab .tab-close-button {
visibility: collapse !important;
}
I found this being more annoying than the "x" being highlighted. Is there a similar thing I can do that only disables the highlighting without hiding the entire button?
Alla svar (1)
You can try one of these rules in userChrome.css to see what works best for you to disable the appearance change if you hover the close X on a tab. You need to close and restart Firefox (e.g. use the button on about:profiles) after modifying userChrome.css.
.tabbrowser-tab:hover .tab-close-button { background-color: transparent !important; color: inherit !important; }
.tabbrowser-tab:hover .tab-close-button { background-color: unset !important; color: unset !important; }
DISCLAIMER: modifications made through a userChrome.css file can stop working as Firefox evolves in new releases, and can "break" the interface in serious ways.