Does this occur on just one or two sites, or does it occur all over the place?

If it's just one or two sites, do you want to post a link to a page demonstrating this problem?

If you see it on multiple sites, could you test in Firefox's Safe Mode? In Safe Mode, Firefox temporarily deactivates extensions, hardware acceleration, and some other advanced features to help you assess whether these are causing the problem.

If Firefox is not running: Hold down the Shift key when starting Firefox.

If Firefox is running: You can restart Firefox in Safe Mode using either:

• "3-bar" menu button > "?" button > Restart with Add-ons Disabled
• Help menu > Restart with Add-ons Disabled

and OK the restart.

Both scenarios: A small dialog should appear. Click "Start in Safe Mode" (not Refresh).

Any improvement? (More info: Diagnose Firefox issues using Troubleshoot Mode)

Thank you. I am now able to click OFF the x on the player that pops out without losing the text on the page. I WISH Firefox wouldn't do things like this in their updates as I DO like to run adblock plus. Just ONE MORE WAY for Firefox to FORCE ads on its customers unfairly.

It's not a Firefox feature!

Safe Mode is a test mode, and the test shows that most likely one of your extensions is causing this. Try removing ALL nonessential and unrecognized extensions on the Add-ons page. Either:

• Ctrl+Shift+a
• "3-bar" menu button (or Tools menu) > Add-ons

In the left column, click Extensions. Then on the right side, if in doubt, remove. Bear in mind that all extensions are optional; none come with Firefox.

Often a link will appear above at least one disabled extension to restart Firefox. You can complete your work on the tab and click one of the links as the last step.

Any improvement?

Note: If an extension is missing a Remove button, it typically was injected externally and can be removed through the Windows Control Panel.

If nothing strikes you as suspicious or the problem continues or returns, can you post your extension list? You can copy/paste it from the support information page. Either:

• "3-bar" menu button > "?" button > Troubleshooting Information
• (menu bar) Help > Troubleshooting Information
• type or paste about:support in the address bar and press Enter

Scroll down to the Extensions heading, then select from there through the table the follows, and paste into a reply. It will look a bit messy, but that's okay, we're used to it. Hopefully we can spot the culprit and you can remove it and be on your way.