I updated from 16.04. All files were downloaded, but after installation for several hours(almost all were installed), update manager froze of about 3 hours. I killed the upgrade manager and rebooted. Now it starts in ubuntu 18.04, but none of the characters are visible as shown in image below:
even the command line is not visible:
Only xterm is visible. Chrome is also working fine.
fc-cache -fr
worked! Thanks. – Devesh Anand Srivastava Jun 19 '20 at 16:13