Avast currently will not remove Passshow even after browser clean-up and the deepest boot scans. I don’t think it considers Passshow a threat even though it often hitch-hikes onto a computer pretty covertly and can completely ruin the browsing experience with masses of unwanted advertising and redirections and it populates itself widely across browsers without easy un-installation.
Surely this is exactly what most people would like to be protected from when buying a security ‘suite’.
I have been very disappointed that Avast ( which has been great- Grimefighter not withstanding) could not remove Passshow :o and I had to go to Malwarebytes to get the job done ( in trial mode I’m happy to say).