I use Camtasia for grading my students animation homework. I've noticed on both 2019.4 and now with 2019.5 that if I have Camtasia open and perhaps leave my desktop for 15 mins or more or even just working but with multiple recordings that are referenced in the media bin, Camtasia will go into this "Click the mouse, spin the beach ball, do nothing, click the mouse, spin the beach ball, do nothing" mode. This becomes completely unusable. The only solution is to hope you can save, then quit and start again. I have no idea what it is. doing but IMHO this is a serious bug because it makes the program completely unusable. Perhaps there is some preference I've not set properly and I'd like to know what that is but this is very annoying. My machine is a fairly new 2018 MacBook Pro, 32Gb Ram, 2Tb disk (about 40% full). I have lots of memory and lots of available disk space. My recordings are only about 3-5 mins in length and at any one grading session I might get up to about 8-10 sessions and then quit. I actually don't keep the source as I write out the file and move on.