Adobe Animate keeps crashing after black screen

[Kenjix5C94]

 This happens where everything turns black, a white window appears and doesn't display anything. I can click on things but there is no response. I have no choice but to force close it through task manager and somtimes it doesn't reopen recover files and I lose hours of work. This is something that happens often and I don't know the problem. 

[kglad]

first, save your fla's with increasing version number so you never lose more than a few minutes of work.  ie, save project1_v000.fla, project1_v001.fla, etc

next, see if you can stop the crashes by resetting your an preferences, https://helpx.adobe.com/animate/using/set-preferences.html

[Nick Gioia]

Have you tried to upgrade to 21.0.4?