I am using FF 58.0.2 which starts on PC boot up. On this first start up of FF some times when you click on any of the tabs on the tab bar the tab drop down will be black with no text in the panel. It will show some of the icons and any key board controls such as ctrl+j. Normally the tab drop down have a grey background. Any functions work OK when you click the right spot in the drop down. Closing FF and restarting FF clears the problem. I have removed the tick on recommended performance settings and have just unticked the hardware acceleration but don't know if that works or not yet. This is an intermittent problem and only on startup. The home screen is the correct color, only the tab drop downs are a problem. Have tried to attach a screen print saved to Paint showing bookmarks tab, but I couldn't get it to copy into this text or by browsing at the add images heading.