System 2012 iMac
MacOS Sierra 12.1
Latest version of Avast, properly updated 12.3 (47217)
Full System Scan (I run every week!), now starts properly, and reaches 100%; but then continues forever. Had to force-quit the application after 22-hours!
This is a brand new bug, and needs some attention. Termination of the full-system-scan, at the appropriate point would be helpful !