I recently upgraded my system from 19.04 to 19.10. I spent about a day and a half using the new system (19.10)... I added a few software platforms (e.g., Eclipse, Android Studio, etc.)
Now (without knowing what I may have done to create this) once the login screen is presented, I enter a valid username and password... The screen appears normal, with the system going to work (same as before)... Unlike before, I can leave it in that state for an hour with no seeming return..
I can access my TTYs (tty2-tty6)... But I don't know how to troubleshoot...
Can someone get me started, please?
UPDATE (2019-10-22) After changing an entry in grub.cfg (removed the line about background image), I no longer get a login screen. An obvious pause (hang?) happens... From which I can now access TTY 1 - TTY 6 (previously, I could access all BUT TTY1.)
How can I recover?
After many years using Ubuntu, this has been my most-difficult problem. 19.10 appears to be super-fragile. I have reinstalled 19.04. Once I'm convinced 19.10 is more stable, I'll retry it.