hello, it sounds like a theme or extension might be interfering here. please try launching firefox in safe mode once and see if the issue is occurring there too. in case it's working correctly, please go to firefox > addons > extensions and disable/remove any extension that look suspicious/you didn't install intentionally or that might interfere with the tab loading behaviour.

Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems

We may be seeing a few more such problems than is usual, it will help others if you post back when you find a solution.

If safe mode works and it proves to be a particular theme or add-on what is the specific extension causing the problem.

Or is your problem graphics related and solved with disabling hardware acceleration.

I went to safe mode and removed the add-ons that were suspicious but it didn't help. But when I reset Firefox, my problem was solved. Thanks for the help :)

Glad it is working again, thanks for posting back.

We do not know at this stage what part of FirefoxReset solved your problem.

We do not have full information aside of initial extensions and changed preferences however as you try to get Firefox back to the state before the ResetFirefox you may discover a particular preference or add-on is the cause of the problem if so maybe you would post back again with a further update.

I pressed the Firefox button at the top left corner and went to help and pressed Firefox reset with disabled add-ons. There weren't many add-ons, only a google toolbar and a wx-downloader. That's all I did to bring it back.