This could be a problem with High Contrast Mode on Mac.

See "New" in the release notes.

• https://www.mozilla.org/en-US/firefox/91.0.1/releasenotes/

Firefox now automatically enables High Contrast Mode when "Increase Contrast" is checked on MacOS in the Accessibility settings.

Make sure you allow pages to choose their own colors.

• Settings -> General: Fonts & Colors -> Colors: "Override the colors specified by the page with my selections above" => Never
• https://support.mozilla.org/en-US/kb/disable-high-contrast-mode-firefox

Thank you, but that sis not do anything, unless I need to restart FireFox?

I restarted, and still the same :(

Can you clarify what changes you made ?

Did you change this setting to Never ?

• Settings -> General: Fonts & Colors -> Colors: "Override the colors specified by the page with your selections above" => Never
• https://support.mozilla.org/en-US/kb/disable-high-contrast-mode-firefox

You can try these steps in case of issues with webpages:

You can reload webpage(s) and bypass the cache to refresh possibly outdated or corrupted files.

• hold down the Shift key and left-click the Reload button
• press "Ctrl + F5" or press "Ctrl + Shift + R" (Windows,Linux)
• press "Command + Shift + R" (Mac)

Clear the Cache and remove the Cookies for websites that cause problems via the "3-bar" Firefox menu button (Settings).

"Remove the Cookies" for websites that cause problems:

• Settings -> Privacy & Security
  Cookies and Site Data: "Manage Data"

"Clear the Cache":

• Settings -> Privacy & Security
  Cookies and Site Data -> Clear Data -> Cached Web Content: Clear

Start Firefox in Troubleshoot Mode to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration or userChrome.css is causing the problem.

• switch to the DEFAULT theme: "3-bar" menu button or Tools -> Add-ons -> Themes
• do NOT click the "Refresh Firefox" button on the Troubleshoot Mode start window

• https://support.mozilla.org/en-US/kb/diagnose-firefox-issues-using-troubleshoot-mode
• https://support.mozilla.org/en-US/kb/troubleshoot-extensions-themes-to-fix-problems

• https://support.mozilla.org/en-US/kb/enhanced-tracking-protection-firefox-desktop
• https://support.mozilla.org/en-US/kb/smartblock-enhanced-tracking-protection
• https://support.mozilla.org/en-US/kb/trackers-and-scripts-firefox-blocks-enhanced-track

1) Did you change this setting to Never ? Yes 2) Clear the Cache and remove the Cookies for websites that cause problems via the "3-bar" Firefox menu button (Settings). - not a per page issue - happens on all pages. I cleared the cache = I did this > Settings -> Privacy & Security Cookies and Site Data -> Clear Data -> Cached Web Content: Clear 3) Start Firefox in Troubleshoot Mode- I did this 4) to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration or userChrome.css is causing the problem. - I tried this - Nothing showed up, but I don't know what I was looking for. 5) switch to the DEFAULT theme: "3-bar" menu button or Tools -> Add-ons -> Themes = there is not default theme to choose 6) I am in dark mode now as this white is too crazy, still not right

You did close Firefox via "Firefox -> Quit Firefox" as on Mac it is possible to close all open windows, but have the menu bar visible ?

Cor-el:

It is fixed! Not sure what made it finally switch back, but it is all good! thank you for your time and help!! It is greatly appreciated!