That message is a iTune and Microsoft software issue don't see any message stating in the screenshot that it's a firefox browser issue.

Yes, I agree. I don't care much about Itunes working. but I want to get FFx back. Edge is making me nauseous. Should I uninstall & reinstall again ? [ NO - DON'T DO IT - SEE "CHOSEN SOLUTION" ]

installed new itunes [ wanted me to close firefox ] I did --- after that firefox running but no websites so I reinstalled FFx no help , - firefox running but no websites --- i'm on Edge now but want to get FFx back. Prior to reistalling FFx [ from Midrosoft store ] the following message came up on FFX --- see attached image

This can be due to issues caused by a corrupted or incomplete Visual C++ installation that is missing runtime components (Redistributable Packages) required by Firefox, especially VCRUNTIME140_1.dll.

See "Visual Studio 2015, 2017 and 2019": https://support.microsoft.com/en-us/help/2977003/the-latest-supported-visual-c-downloads

Then reboot the system.

Thanks, James - I was travelling all day yesterday. I assume you suggest that I pick a link and install it. then reboot.

--- here's what I had done recently : ran FFx troubleshooting , selected 'refresh" - which processed but left me with the same problem [ now default FFx ]. I'm trying now to lose profile, hisitory, bookmarks. [ rebooted Laptop a few times.] --- FFx is running; If I enter some typical sites I would access it brings up several reasonable options ; but whatever I select the display area remains the same white that you see in the background of the image here. --- I also noticed this message to me that my account is disconnected I do have an account - I have passwd, and I am on this support page. So I'm wondering if I hit some key combination that started this problem . see attached image of that. [ could it be decades that I've been using FFx - had account - with almost no problems ? ]

Thanks for being there - I hope some of this info sheds some light on the problem .

MAKE THAT "I'm trying not to lose profile, hisitory, bookmarks.?

Thanks to all [ James :) :) ] I am responding from Firefox [ no losses ] !!! The link you advised has done the trick ! Goodbye to Edge .