Try Firefox Safe Mode to see if the problem goes away. Safe Mode is a troubleshooting mode, which disables most add-ons.

(If you're not using it, switch to the Default theme.)

• Open the Help menu and click on the Restart with Add-ons Disabled... menu item while Firefox is running.

Once you get the pop-up, just select "'Start in Safe Mode"

If the issue is not present in Firefox Safe Mode, your problem is probably caused by an extension, and you need to figure out which one. Please follow the Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems article for that.

To exit the Firefox Safe Mode, just close Firefox and wait a few seconds before opening Firefox for normal use again.

Please report back soon.

Hi ComputerWhiz,

Thank you for a speedy response :D I just tried the Safe Mode on Firefox and unfortunately the problem persists.

I've attached a screenshot of the weird display glitch.

Since the issue continues when you run Firefox in Safe Mode, we can rule out any add-on issues.

Please try running a Plugin Check to ensure that all of your plugins are up to date and running correctly.

Also try running a full scan for malware, viruses, and bad registries.

Please report back after completing the above.

Hi ComputerWhiz,

I just performed the Plugin Check - Java needed to be updated, so I did that. Restarted Firefox. Did the check again and everything is now up to date.

Problem still persists.

I've run a scan (virus/malware and general system) and nothing appears out of order.

The Reset Firefox feature can fix many issues by restoring Firefox to its factory default state while saving your essential information. Note: This will cause you to lose any Extensions, Open websites, and some Preferences.

To Reset Firefox do the following:

1. Go to Firefox > Help > Troubleshooting Information.
2. Click the "Reset Firefox" button.
3. Firefox will close and reset. After Firefox is done, it will show a window with the information that is imported. Click Finish.
4. Firefox will open with all factory defaults applied.

Further information can be found in the Refresh Firefox - reset add-ons and settings article.

We hope to hear from you soon.

Hi ComputerWhiz,

Resetting Firefox did the trick! :D All videos are working properly again.

Thank you for your help!

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