@Daniel van Vugt:
You were right; the problem appears to have been related to a shell
extension, but not one of the extensions you suggested I uninstall. The
cause seems to have been the "freon" extension
(https://extensions.gnome.org/extension/841/freon/) which was installed
but disabled. Since
@Sebastien Bacher: journalctl output attached.
@Daniel van Vugt: I'll do so and get back to you.
** Attachment added: "Journal ctl output as requested"
https://bugs.launchpad.net/ubuntu/+source/gnome-shell/+bug/1830255/+attachment/5266185/+files/curjournal.zip
--
You received this bug
Public bug reported:
After the screen is blanked following a few minutes of inactivity, the
UI freezes for about a minute as soon as the password has been entered.
During this time there is a lot of harddisk I/O (close to 100%) until
eventually the UI eventually unlocks and the regular desktop
$ apt-cache policy gnome-shell
gnome-shell:
Installed: 3.28.3+git20190124-0ubuntu18.04.2
Candidate: 3.28.3+git20190124-0ubuntu18.04.2
Version table:
*** 3.28.3+git20190124-0ubuntu18.04.2 500
500 http://us.archive.ubuntu.com/ubuntu bionic-updates/main amd64
Packages
500
