Crashes for me if I try to drag first party widgets into the area with third party ones (Carrot Weather for me) And not a crash, but widgets are somewhat funky on my SE2020. Sometimes I need to go to the first page to hold an app and pick edit home screen, and then go back to the widget screen. They work fine on my wife's 11PM. Another weird thing is I was fooling with the first party weather widget and then it got stuck. No matter what I did, I couldn't get back to the home screen. I could switch to other apps, but it would always go back to the solo weather widget instead of home. And all I could do on the widget was change the location. Had to restart and then was ok again.
I am guessing those old widgets will be removed. There’s no support for them for developers anymore.