This UI sucks so hard - incredibly horrible! Why you not only updated the plugin engine referring to the latest Mozilla guidelines? And partially the blocked/hidden sections came back since v3.0 ....
It's not as simple as "upgrading the plugin engine," large parts of the extension and particularly the user interface had to be rewritten from scratch. More on this here: https://adblockplus.org/blog/the-plan-towards-offering-adblock-plus-for-firefox-as-a-web-extension
