Another place to check for possibly suspicious add-ons is the extensions category.

Open the add-ons page using Ctrl+Shift+a or:

orange Firefox button (or Tools menu) > Add-ons

Then on the left side, click Extensions and disable the ones that are unnecessary or unrecognized.

Usually 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.

Two other things to check:

• Right-click the shortcut you use to start Firefox and click Properties, then check the "Shortcut" tab's "Target" field to make sure the unwanted URL isn't tacked on to the end

• Since your More System Details shows a user.js file in your settings, that may be injecting unwanted settings. Check out this article for more information on how to deal with that: How to fix preferences that won't save

Any luck?

Hello,

Try disabling graphics hardware acceleration. Since this feature was added to Firefox, it has gradually improved, but there still are a few glitches.

You might need to restart Firefox in order for this to take effect, so save all work first (e.g., mail you are composing, online documents you're editing, etc.).

Then perform these steps:

• Click the orange Firefox button at the top left, then select the "Options" button, or, if there is no Firefox button at the top, go to Tools > Options.
• In the Firefox options window click the Advanced tab, then select "General".
• In the settings list, you should find the Use hardware acceleration when available checkbox. Uncheck this checkbox.
• Now, restart Firefox and see if the problems persist.

Additionally, please check for updates for your graphics driver by following the steps mentioned in the following Knowledge base articles:

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

• Upgrade your graphics drivers to use hardware acceleration and WebGL

Did this fix your problems? Please report back to us!

Thank you.