Keep finding this issue whenever I want to share my library with friends who also happen to play Dirty Bomb, it then locks their account out of the game with the message “Scanning for Steam updates” until it kicks them either onto the DB store page, or onto their library page.
I have no idea whether this is a Steam issue or something with Dirty Bomb, but as its only happening with Dirty Bomb I’ll post it here too.
And no, ClientRegistry doesn’t seem to exist any more so that fix has gone.