After last updates the dock is no longer displayed unless i click on 'Activities' top left on the screen. Also when it appears it has a different appearance.
The Ubuntu Dock extension was updated for gnome-shell 3.31.90 which has not migrated out of -proposed yet. I expect the new gnome-shell version to land by early next week.
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I see it's entangled with the glibc transition so hopefully that won't take too long.
I had this problem too, but after I enabled the Developer option and updated the dock is back. Now I have only the gnome-keyring bug LP: #1817128 and a package kit crash, that isn't possible to report.
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