How far have you got? Do you have a userChrome.css file and is it working? I have separate code for font colour and background colour. Which do you want?

Are you using a light theme or a dark theme and what colours do you have in the drop-down menus now? What about the 3 bar menu and the bookmark drop-downs?

Hello Terry , Thank you for your quick reply. Yes I have a userChrome.css working fine. I am using an old firefox theme "blue win 95". As I mentioned , my firefox is 93 version , I did not update because the next updates no longer work my css. I tried numerous examples I found on the web , regretfully , none worked. Terry , I do not need to modify the background or font , all I need is when I hover the opened menu item list to choose an option , I need to highlight it in whatever color I choose. It is very frustrating after numerous attempts , nothing seemed to work. One thing though , the highlight I get is the one my windows uses , you can see it in the picture - just some sort of pale blue enclosure. Hope I've made myself clear. look4

sorry for some reason I am not able to upload the image

I have been unable to change the hover colour there either. This code was pasted recently on this site and worked for the person asking (but not for me).

menupopup > :is(menuitem, menu):hover {
  background-color: Yellow !important;
}

Thanks Terry , it did not work for me either.

I have come across code for hover which works for me in dropdown and popup menus so it may work for you. The colour below is a light blue but you will choose your own of course.

menu:hover, menu[open=true], menuitem:hover, menuitem[_moz-menuactive=true] {
  -moz-appearance: none !important;
  padding: 5px 0px;
  background: #6699ff !important;
}

Hi Terry , Thanks , I have been away for while , so I couldn't write you a note. I already wrote a code that works for me , tried it in FF93 and later FF94 , 95 , it works fine except a problem in FF93 , when I hover the items quickly , I get a second trail of highlight , especially in bookmarks where FF93 has a problem loading all my bookmarks and favicons. I've searched the web and it seems that others also encountered the same problem , slow load of bookmarks. The problem is fixed in FF94 and later. Here is the code : menuitem:hover { background-color: rgba(102, 204, 255,0.9) !important; padding-inline: 0px !important; -moz-appearance: none !important; } menuitem{ padding:0.3px; !important; -moz-appearance: none !important; }

I also tried the one you found , it also works , except when I hover the menu bar the size of the tab becomes higher. Please try the one above and tell me if it works for you too. look4

Thanks, look4. I tried your code. Regrettably, it doesn't work for me.