That kind of advertising is very annoying. Sometimes is it added by the site itself, but if you see it everywhere, more likely, you have a bad extension.

Try disabling ALL nonessential or 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, if in doubt, disable.

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.

Does that cut down those embedded ads?

You may have noticed that some extensions do not have a Remove button. Those were installed externally to Firefox. So for those I suggest:

Open the Windows Control Panel, Uninstall a Program. Click the "Installed on" column heading to group the infections, I mean, additions, by date. This can help in smoking out undisclosed bundle items that snuck in with some software you agreed to install. Take out as much trash as possible here.

1. Start Firefox in safe mode to check if one of the extensions is causing the problem:
   • Firefox in safe mode
   • See Troubleshooting extensions and themes if the problem doesnt occur in safe mode.
2. Malwares can also cause these problems:
   • Problems with malwares
3. You can also use some add-ons to block ads/popups:
   • Adblock Plus
   • Simple Adblock
   • Adblock Plus Pop-up Addon

Could you give us a screenshot of these ads?

• screenshot of the problem

By the way, if you installed the update from a download, can you check your download history for the source? It might be one of those unscrupulous bundling sites that install something that pushes more and more crap onto your computer.