There's a few things that you can try to fix this: * [[Upgrade your graphics drivers to use hardware acceleration and WebGL]] * Download and install Malwarebytes from www.malwarebytes.com and install and run it. Remove anything it finds. * Uninstall any anti-virus on your computer, and use the built in Windows Defender. * Make sure you have installed all Windows Updates. Restart and check again as necessary * [[What is the Accessibility Service Indicator?#w_how-do-i-disable-firefox-accessibility-service|Disable Firefox Accessibility Service]] After doing all the above, please retest and let me know if you have issues still.

Thanks Tyler Downer. Everything looks better than before. I have this situation after upgrading Windows 10 April 2018. Thank you very much.