[Kawasaki]

Quite often recently when I'm using FireFox, a window pops up with the FF icon and the heading: The page at http://performanceoptimizer.com says...

Then it goes on to tell me how I should tune up FF because errors can slow it down. When I click cancel, I still get sent to their page. So now I exit FF and reboot; or switch to Safari. Can anyone tell me what's happening and preferably how to stop it? Even if it a legitimate company, it is so rude and intrusive, I don't think I want to do business with them, unless someone can make a great case for their service.

[ghoti]

That's a pop-up ad, not a message from FireFox. It also doesn't matter where you click, it will all take you to their site. Just close the window (Cmd-W or click the red button on the window frame) and then go into FireFox' preferences and activate the popup-blocker. You can always allow popups for those sites that absolutely need them (this is called "whitelisting"). You could also consider avoiding websites that have such rude and annoying advertising.

[Kawasaki]

Originally Posted by ghoti; That's a pop-up ad, not a message from FireFox. It also doesn't matter where you click, it will all take you to their site. Just close the window (Cmd-W or click the red button on the window frame) and then go into FireFox' preferences and activate the popup-blocker. You can always allow popups for those sites that absolutely need them (this is called "whitelisting"). You could also consider avoiding websites that have such rude and annoying advertising.

Thanks for the response. As far as I understand, I already have the popup window blocker active (FF Preferences - Contents - Block popup windows. Correct? In fact, this has always been 'ticked'. I did have two exceptions which were unrelated; I've removed these now, just in case. Similarly, I have been exiting FF via the red button for some time now, whenever the intrusion happens; but soon after it occasionally returns several times for a spell, then will disappear for maybe several weeks before reappearing again. It is annoying. I'm surprised there are not more users of FF experiencing this, which makes me think I have made myself vulnerable in some way. Any other suggestions?

[Dave]

Turn off Javascript and plugins

[torifile]

There are sites that have popup windows appear when you click on a *link*, bypassing the "block popups" preference because you've "requested" that popup. There's nothing you can do but turn off javascript but then you lose lots of functionality. Just don't go to that site anymore.

[tsa]

Or use the Adblock plugin to block the script that pops up the window.