Anti spam, whitelist, blacklist button disappeared from ribbon in Outlook 2013

It seems that my anti spam, whitelist and blacklist buttons have disappeared from my Outlook 2013 ribbon. I didn’t do anything different but I just noticed a few minutes ago that the buttons are gone. I tried adding them in but I don’t even see the option for Avast in the list. I am running Avast Internet Security.

Any help is appreciated.

thanks!

Known bug, see: https://forum.avast.com/index.php?topic=224223.msg1489781#msg1489781