Freshly installed Xubuntu 20.04 shows black screen instead of login screen upon boot on Lenovo Ideapad L340-17API. It is not possible to chvt to text terminal when boot is stuck on black screen.

Booting with 'nomodeset' kernel option works properly but is not an option (e.g. screen brightness is not adjustable in this case).

Another workaround is to ssh to laptop and run systemctl restart display-manager.service. After 5-10 seconds upon executing this command perfectly working login screen ...