There is another way to start a Refresh:

If Firefox is not running: Hold down the Shift key when starting Firefox.

If Firefox is running: You can use either:

• "3-bar" menu button > "?" button > Restart with Add-ons Disabled
• Help menu > Restart with Add-ons Disabled

and OK the restart.

Both scenarios: A small dialog should appear with the options to "Start in Safe Mode" -- a useful testing tool that you might try if you haven't already seen whether that helps with your issues -- and Refresh

Does that button work?

Can you give more details about the issues you encounter in Firefox?