Are you sure the browser window isn't iconized?

If this isn't the case, follow the below instructions.

The Refresh feature (called "Reset" in older Firefox versions) 

can fix many issues by restoring Firefox to its factory default state while saving your bookmarks, history, passwords, cookies, and other essential information.

Note: When you use this feature, you will lose any extensions, toolbar customizations, and some preferences. See the Refresh Firefox - reset add-ons and settings article for more information.

To Refresh Firefox:

1. Open the Troubleshooting Information page using one of these methods:
   • Click the menu button , click help and select Troubleshooting Information. A new tab containing your troubleshooting information should open.
   • If you're unable to access the Help menu, type about:support in your address bar to bring up the Troubleshooting Information page.
2. At the top right corner of the page, you should see a button that says "Refresh Firefox" ("Reset Firefox" in older Firefox versions). Click on it.
3. Firefox will close. After the refresh process is completed, Firefox will show a window with the information that is imported.
4. Click Finish and Firefox will reopen.

Did this fix the problem? Please report back to us!

Thank you.

Hi Thanks,

I didn’t want to really do that because I might loose some of my customisations through userChrome.css. So I have removed userChrome.css from my profile and restarted FF. I can now see that the Back button and others …. Forward and Home buttons are on a line below the Red, Orange, Green buttons. So the problem is in my userChrome CSS.

I will need to review each item in there, to see what each does to the new FF version. I have been adding to that over many years and there will be old defunct items having a negative effect.

Many thanks for prompting me to think in this direction.

Kind regards

AnotherDesign

You're welcome, glad I could help.

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