- This is not a solution because I need the add-ons working

 - https://support.mozilla.org/en-US/questions/1099128 (Why doesn't Windows 10 taskbar stay on top when browsing with Firefox?)
 - https://support.mozilla.org/en-US/questions/1077468 (Minimize, maximize and close buttons are missing)
 - https://support.mozilla.org/en-US/questions/1178962 (Make close buttons always appear)

FireFox did an automatic update to version 57. After that, several issues occurred. The two that I cannot fix are: 1. The Minimize, Maximize/Restore, and Close buttons on the title bar are missing 2. The Browser window in maximized mode overlaps (hides) the taskbar which is located at the bottom of the screen (note: the taskbar appears correctly when any other application is in focus) What I've tried: a. Changed the Default theme to the Light theme (in the Default theme, the title bar is transparent and unusable) - but still no buttons b. Deleted the xulstore.json and localstore.rdf to have FireFox recreate those - no effect c. The taskbar is configured to always be displayed and locked to the bottom of the screen - as mentioned, there is no issue when any other application has focus d. The screen is NOT in full screen mode (i.e. F11) e. I've started FireFox in Safe mode and everything appears normal (buttons and taskbar are OK) - This is not a solution because I need the add-ons working f. I've started FireFox in Normal mode with all add-ons disabled - no effect (buttons still missing and no taskbar) g. I've added .titlebar-button, .titlebar-button > .toolbarbutton-icon, .titlebar-button:hover, #titlebar-close:hover, and #titlebar-close:hover styles to userChrome.css - no effect h. Tried the suggestions in the following articles - no effect - https://support.mozilla.org/en-US/questions/1099128 (Why doesn't Windows 10 taskbar stay on top when browsing with Firefox?) - https://support.mozilla.org/en-US/questions/1077468 (Minimize, maximize and close buttons are missing) - https://support.mozilla.org/en-US/questions/1178962 (Make close buttons always appear)