Stop attack sites from being able to change your browser position and layout with advanced JavaScript restrictions: https://support.mozilla.com/en-US/kb/Options+window+-+Content+panel#Advanced_JavaScript_Settings

You can use the AlertCheck add-on to be able to break out of malicious pop up dialog alerts.

Future versions of Firefox may have the ability to move tabs that have popped up annoying dialogs.

I have the same problem -I force quit Firefox. But, when I opened it again, I got the same message. When I opened it a third time, it just said, "well this is embarassing, we can't reconstruct your tabs".. basically.. do you want to start a new sesssion or should we open these tabs (list of tabs, including AV). I said start a new session. But, now I'm concerned about using Firefox at all on that computer (I'm on a different computer now). However, it's necessary for work. What happened? Do I need to worry? thanks,

By the way, I checked the Content and Security tabs in Preferences and "Block reported attack sites" box is checked as are the "block pop up windows and Enable Javascript".

Hi Charles,

You just stumbled across an attack site, trying to get you to install a Fake AV, malware.

These sites are all over the web, as long as you didn't run any files from that site, you'll be fine.

The malware authors move very fast, so not every attack site is going to be caught by the built in protection right away. The URL mentioned by the original poster is now a reported attack site, however.

By the way, you can use the check marks on the Session Restore page to select/deselect pages to restore. See Restore previous session - Configure when Firefox shows your most recent tabs and windows.

Thanks.

This popup appears about once a week in my Firefox too. The small window says

The page at e.g. http://www.histats.com says:

triangle ! funzone

     box OK

Funzone is only one of the short strings of snot that appear. On clicking the OK button it merely dings and changes the string. On closing with redX the same thing happens and cannot close the popup.

I have to use Task Manager to close Firefox. On restarting Firefox the popup usually is gone and does not appear for days. This time it returns immediately.

These popup message windows with an OK-button in it together with a simple text message, are NOT being blocked at all, no matter the settings. These message windows are being requested around 500 000 to a million times in a row. Then one have to click "ok" or close every single one of them, one by one as they keep reappearing.