I don’t know if anyone found this or post this before. I search and found nothing so I decide to post.
I use avast to block dozen of site, including facebook. One day I visit my university site with my Firefox 4 and enable IE tab since it not support other browser. And then, accidentally, click facebook button, and go straight to the suppose-to-be blocked site! :o
I test Site Blocking with IE, Firefox, Opera, Safari, Chrome, and Maxthon. It’s all latest version and Site Blocking work perfectly. But now I found two way to bypass Site blocking, IE Tab add-on in firefow, and IETester, program for testing site with different version of IE.