Is there an URL shown on the location bar?

Start Firefox in Safe Mode to check if one of the extensions (Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem.

• Switch to the DEFAULT theme: Firefox/Tools > Add-ons > Appearance
• Do NOT click the Reset button on the Safe Mode start window

• https://support.mozilla.org/kb/Safe+Mode
• https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes

You can check for problems with the sessionstore.js and sessionstore.bak files in the Firefox profile folder that store session data.

Rename (or delete) the sessionstore.js file and possible sessionstore-##.js files with a number and sessionstore.bak in the Firefox profile folder.

• Help > Troubleshooting Information > Profile Directory: Show Folder (Linux: Open Directory; Mac: Show in Finder)
• http://kb.mozillazine.org/Profile_folder_-_Firefox
• http://kb.mozillazine.org/Multiple_profile_files_created

Deleting sessionstore.js will cause App Tabs and Tab Groups and open and closed (undo) tabs to get lost and you will have to recreate them (make a note or bookmark them if possible).

Yes, URL show in address bar. I always use DEFAULT theme. Safe mode not help.

Can you open this page in a new tab?

Does this also happen with built-in about: pages (see about:about for more about pages) like the about:home page?

Try to open a new window to see if it works in that window.

Did you try to rename or delete the sessionstore.js file?

cannot open about: pages

can open about:about

about:home works fine.

delete sessionstore.js fixed.