How to permanently and irrevocably block websites on Firefox? [closed]

With Internet Explorer it's simple: you go to the settings menu, add websites you want to block, just randomly enter a sequence of letters and numbers so you cannot ever know the password, and it's done. (You could uninstall and re-install Explorer, but that's too big a pain to actually do that.)

With Firefox, its a different question. The main method is to add certain add-ons, like blocksite. However, add-ons like this have one FATAL flaw: you just deactivate the add-on and restart Firefox (which in all takes just a few seconds), et voilá... Too easy a by-pass to block you from not visiting certain websites.

I need to work on my bloody thesis, and seriously need to block like 10 websites. HOW?! Please help.

PS: can't have anything to do with the router, since there are several people using it, and adding URLs in the HOST also ain't good enough...

Install a proxy server that blocks requests from your machine to the websites. If I'm really reading that you're addicting to a series of sites to the point where it interferes with your work or life, you might want to consider therapy as well. Seriously. If it's interfering with your life, you need to seek assistance.

There is such a thing as Internet Addiction...

Given the apparent lack of self-control, register for OpenDNS.org and configure your machine to use their nameservers. Then blacklist the sites you can't keep yourself away from. Added bonus: works for everything. No need to jack around with reinstalling IE.

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