Is it the whole window blinking, or part of it?
What were you doing at the time? surfing, watching a clip, reading something . . . .
Is this with all websites/pages, some, a few?

Did you try to close and restart Firefox or reboot the computer ?

Hello aslamsherwani,

In other threads (mainly on Reddit) I saw some people mention that upgrading their graphics drivers solved the problem;   for others disabling hardware acceleration did
the trick :

Upgrade your graphics drivers to use hardware acceleration and WebGL

Worth a try .....

I use for seeing mails, viewing recorded videos , Reading eBooks, Problem started three days ago when I installed latest version 77.01 64 bit . I refreshed, troubleshooted safe mode, rebooted. uninstalled and reinstalled several time. During trouble shoot there was indication that there is problem in java installed. I am ready if I get some easy Link which checks driver and update my drivers. Last eavning trouble started after 2 hours, Today it was started as soon as I opened Firefox, I posted question using edge. At the moment it is alright and able to post this. The article above is difficult to follow. In Device manger I found my laptop but I am afraid to delete and restart computer and loose/disturb my other browsrs Edge and hrome. Waiting for reply.

You can boot the computer in Windows Safe Mode with network support (press F8 on the boot screen or hold down the Shift key) to see if that has effect.

• https://www.bleepingcomputer.com/tutorials/how-to-start-windows-in-safe-mode/
• https://www.7tutorials.com/4-ways-boot-safe-mode-windows-10