I’ve noticed my scan progress bar (as well as the number indicator) reaches 24% in Avast Security, but then stays there for several hours while continuing to apparently scan more items. It then crashes. I uninstalled, then updated via the Avast website. Problem repeated. Just did so again via beta channel. Third time’s the charm? I have a Mac Pro (late 2013) with a 3.7 xeon, 32 gb, d300 2 GB graphics, running Catalina 10.15. And the beta OS may be the real problem, but I thought it worth mentioning. I’m running 13.13 right now with virus def. 19072804.