Firefox freezes on "Probem loading page / Server not found" event...

Hi everyone,

I have a major problem/bug with Firefox portable, and I subscribed to the forum hoping that I am not the only one who had this issue, and hopefully that someone has a cure for it.

Symptoms:

• When I enter a URL that does not exist or a URL whose server is down, Firefox portable freezes for about 15-30 seconds before I finally get the page that says "Problem loading page / Server not found".

Frequency:

• Always.

Variants/examples:

• If I have many tabs open, and I enter a different URL in each tab, all the websites will load simultaneously, however if one of the URLs is unavailable and gets the "Problem loading page" error, when I will click on this tab, the WHOLE browser and all of its other windows (download window, other normal windows) will freeze for about 15-30 seconds, before the tab shows up with the "server not found" headline.
• If I have many tabs open, and there is one of them which has already had the error "problem loading page", EVERY time I will go back to this tab, the browser will freeze, even if the tab has contacted the site two days ago and has finished loading since that time. In fact, while writing this, I have an active tab on my browser on which I entered a random unavailable URL, and if I click on it right now, my browser will freeze.
• Sometimes, I get the same problem with downloads. For example, if a download link is broken, it would do the exact same thing. But I also had a similar problem with a download that is long to start. For example, I click on a download link, but the download doesn't start immediately because of heavy server load, then the browser freezes until the download finally starts or fail to start.

Severity of bug:

• VERY annoying.

Other useful information:

• This is not a computer issue. My computer is a Athlon X2 2.4Ghz, with 2Gig of ram, and I looked carefully to the CPU usage to make sure it is not 100% while the bug occurs, and everything looks normal.
• I have a lot of add-ons on my Firefox (some of those I don't even use!)... could that be the problem?
  • ColorZilla, DOM Inspector, Firebug, Foxmarks, Header Spy, IE Tab, IE View Lite, ........
• I don't think it is a Windows issue. I reinstalled the non-portable version of Firefox on my machine (without the add-ons and skins however), and I tried to recreate the bug, but everything was working fine, without the freezing.

Please help me... I love using Firefox portable, because I can work on my computer at home and on my laptop and just take all my settings with me, but this bug is so annoying that I'll have to go back to normal Firefox I think.

Thanks for your help.

Phil