I cannot sign-in or comment thru links provided on wab website, so i have to do it here.
So, it's true... the redirect glitch is directly related to setting Firefox to clear history upon closing. Any other combination of settings seem to work fine. It appears there is no immediate solution other than to not use the extension.
I just found a possible fix and have updated it in the thread: https://jasonsavard.com/forum/discussion/2768/i-think-webmail-ad-blocker-hijacked-my-start-page#latest
