Since I switched to SW 2019 I find the same problem as the 2014 version but that I didn't have in SW 2018, that is to say that after a while you click on new part or mpe, for example, and nothing happens. So I had to close SW and re-open it for it to work.
It's as if the buttons no longer work nor the small file open, but I can open by dragging for example for an existing part, but create one.
But like many of us we close SW from time to time to purge the memory to avoid crashes is less annoying, on the other hand I fill those who are on large assemblies.
In fact, I found a trick so that I don't have to close and reopen Sw. When the bug occurs, you just have to open an MEP of an already drawn part via open ==> browse the recent documents and then you have access to the new documents again. For the moment it's the only thing I've found.
Thanks for the tip because otherwise it makes me lose the last modifications? Not to mention that when the system starts to slip or freeze, the automatic save seems to no longer work. As a result, half an hour or an hour can be lost. Obviously it's always when you do something that you shouldn't lose that it waffles ;-( (because of that damn Murphy)