Every time I reboot my Mac (running OS X Mavericks), the Avast extension reinstalls itself on my copy of Google Chrome (dev version). I know what I’m doing when I search the web. I don’t need the extension to tell me whats safe to view and I want to keep Avast from installing the extension.
Dont really know how a Mac OS works but if you can go to where you go to uninstall a program. In there will be an option to either repair, change whats installed or remove avast!. Click the change tab and deselect the browser protection as that is the extension addon.