@Steve I did not.

Screenshot from 2022-09-26 19-36-11.png Edit (149.8 KiB, image/png)

@Simon Here goes, although now it just shows both at 9.7, and 9.9 not yet available. Before I downgraded libc6 it obviously showed libc6 at 9.9.

I also tried to reproduce the issue in a fresh VM, but those kept getting 9.9 for all the packages, so installing build-essential caused no issues.

I don’t have in-depth knowledge about phased updates, but this looked like as if downloading the updates during installation was not yet affected by phased updates (and hence got libc 9.9), but, after the installation was completed, the system got cast into a ”still at 9.7” group of phased updates, and so libc6-dev (et al) could not be installed.

Just got hit by the same issue in a VM after a fresh install of 20.04.5. I chose ”Minimal installation”, ticked ”Download updates while installing”, and installed the remaining updates post-install.

After that the first thing I tried to do was to install build-essential, which failed, because the version of libc6 was out of sync with the rest of the libc6* packages: libc6 was already at 2.31-0ubuntu9.9, while e.g. libc6-dev was still only available as 2.31-0ubuntu9.7.

I tried switching from my local archive (fi.archive.ubuntu.com) to the main one (archive.ubuntu.com), but that made no difference. I had to downgrade libc6 to 2.31-0ubuntu9.7 to be able to install build-essential.

-s (silent) is also undocumented. There’s a confusing distinction between it and -q (quiet), where the latter isn’t quiet in the usual sense; -s is needed to silence non-error output entirely. There’s useless output even when called entirely without options:

    $ pngcrush 
    CPU time decode 0.000000, encode 0.000000, other 0.000000, total 0.000002 sec
    $ pngcrush -q
    CPU time decode 0.000000, encode 0.000000, other 0.000000, total 0.000002 sec
    $ pngcrush -s
    $

This is pngcrush 1.8.13-0.1 on focal.

Seems to be fixed in VLC 3.0.9.2-1 (Ubuntu 20.04); at least I haven’t been able to reproduce it anymore.

Same ”double free or corruption (!prev)” reproducible here too (VLC 3.0.9.2-1, Ubuntu 20.04), even more easily: the position doesn’t matter, and the first attempt to screenshot is already enough to trigger the issue.

I came across this when trying to screenshot a Superman cartoon I downloaded from Internet Archive [1].

* [1] https://archive.org/download/dom-6746superman-episode7-theundergroundworld512kb/dom-6746superman-episode7-theundergroundworld512kb.mp4

There’s no gnome-shell-extension-dashtodock package for focal [1], but I did try with Dash to Dock from extensions.gnome.org, and could not reproduce the issue with it. I tried with the default settings, as well as after recreating the look & feel of Ubuntu Dock as much as possible.

Dash to Dock has customizable action for the scroll (to either switch workspaces or windows, or to do nothing), and all of those also worked just as expected.

I also noticed that using the two finger scroll function of the touchpad on my laptop does *not* trigger this (whereas using the mouse on it does).

* [1] https://packages.ubuntu.com/search?keywords=gnome-shell-extension-dashtodock

Do you want another log for that? Because (as I already mentioned above), this also reproduces when using a newly-created user, so that means no unsupported extensions.

I can reproduce the crash at will with the steps I listed above, so I don’t have to wait for it to happen. It also doesn’t forcibly log me out, so I can enter those commands by just having a terminal window present when I trigger the issue. But I logged out here (after triggering) anyway since you instructed me to log in, in case it matters.

Also, there’s lots of noise in these from Boinc, thanks to #1876313.

1. There’s nothing in /var/crash
2. There are no reports on the page for this computer.
3. Done, still nothing in /var/crash.

I don’t know if this means it’s not a true crash, although visually all the indications are there.

I also verified that this reproduces when using a newly-created user (with the only change from defaults for it being switching to Wayland), and also on another computer (also running 20.04). I am limited to using the one mouse that I have, so that all testing so far has been with the same mouse.