When upgrading to 2019.2 (paid edition) I was asked if I want to import 2019.1 settings.
No errors were given.
Upon restart, I saw that Xmx was reset to 750 mb from the 4gb setting I had prior. I got a "running low on memory" error and had to re-adjust the settings.
I don't know what other settings were missed on upgrade, is there a way to check for that?