I recently upgraded Firefox and discovered that highlighted text was no longer showing up! Text would still be highlighted (I can copy / paste to verify), but both in edit controls and on the page itself, highlighting just wasn't working. Every other application worked fine.
1 Answer
The solution was to go to about:config and add the following string values:
ui.textHighlightBackground : #c0c0c0
ui.textHighlightForeground : #000
ui.textSelectBackground : #c0c0c0
ui.textSelectForeground : #000
You can, of course, customize these colors to your liking. #c0c0c0 is a nice neutral gray, while #000 is of course straight black.