I've tried the suggestion described in Cannot log in after update to 19.04 to no avail.
$ sudo apt install gnome-session gnome
Still stuck in bootloop though. I double-checked space left in the home folder as well. Plenty available still with 29% Use as suggested here.
@milso suggested on https://askubuntu.com/a/1135250/702968 look at /var/log/syslog and check if you see some Gnome crash stacktrace.
This is what
tail /var/log/syslog produced after my most recent attempt to log in:
gnome-shell: The offending signal was destroy on Gjs_DateMenuButton 0x55c82a2e55c0. org.gnome.Shell.desktop:(EE) failed to read Wayland events: Connection reset by peer gnome-session: gnome-session-binary: WARNING: App 'org.gnome.Shell.desktop' exited with code 1 gnome-session-binary: Unrecoverable failure in required component org.gnome.Shell.desktop gnome-session-binary: WARNING: App 'org.gnome.Shell.desktop' exited with code 1 at-spi-bus-launcher: XIO: fatal IO error 11 (Resource temporarily unavailable) on X server ":0" at-spi-bus-launcher: after 21 requests (21 known processed) with 0 events remaining. gdm3: GdmDisplay: display lasted 1.185092 seconds systemd: session-9.scope: Succeeded. kernel: [ 880.696202] logitech=hidpp-device 0003:046D:101A.0006 multiplier = 8
I was able to adduser and log in. Not sure how to proceed from there in order to get primary user logged in.
Following steps delineated here, I was able to give my new user sudo privileges using
usermod -aG sudo username. I now just use the secondary account. Not too much of an inconvenience. But I will welcome and try any suggestions to fix primary account login loop issue.