Accidentally uninstalled an important package in Debian Sid with KDE, transparency no longer working
Hi everyone, I ran apt full-upgrade last month and accidentally deleted a couple packages that weren't supposed to be removed, due to me not paying enough attention. I could recover most of the system just fine, since most of the missing features and related packages were obvious to me. However, I still couldn't figure out why transparency is not working on KDE, both in Wayland and X. I suspected it could be a missing compositor, but libwayland and libqt6waylandcompositor6 (and related packages) are all installed (and that wouldn't explain why it isn't also working on X).
I have attached a screenshot to illustrate what I mean.
I would appreciate if anyone could help me figure out what package might be missing that is causing this issue. Thanks in advance!
EDIT: Thank you so much everyone! I finally solved my problem. I just had to replace libqt5quick5-gles by libqt5quick5 (non gles version).
if you don't have any backups (like normal people do), check the logs of the package manager. for example /var/log/apt/history.log should have a neat list of operations with timestamps and packages.
Most people don't really get out their way to set up backup manually. Either system should try really hard to avoid corruption or implement a recovery system. Ideally both.
Well, the Linux world is moving towards btrfs and zero-setup automatic snapshots. Those would have made it trivial to rollback a broken update like that. Unfortunaly, it's still going to take a few years before Debian makes the move...
You don't need to get out of your way. You can, for example, just tar --one-file-system, clonezilla or rsync or maybe even drag and drop copy all your important file systems on a USB HD, USB stick or cloud storage that you then check and unplug/unmount.
This is very easy and can run in the background while you do some other stuff. Even if the backup isn't good and for example doesn't have proper permissions, because you drag and drop copied, it will have the info required to reinstall and restore the exact system you had at the time of the backup.
I do store regular backups of this machine, but not of /var. I can always reinstall Debian (or whatever other distro), while keeping other relevant configs intact (stored in the backups) and not lose any critical data.
I commented below that I did check /var/log/dpkg.log, but it didn't help much due to the high number of packages removed that day.
At this point I am more curious to learn more about KDE and what is causing the problem, since other desktop environments (I installed mate) seem to work fine.
I audibly laughed at this. I actually knew I was entering treacherous waters by running apt full-upgrade in Sid, but still thought "well, we'll see..."
Are you on BTRFS? If so maybe you could restore to a snapshot prior to the apt upgrade?
I'm not very familiar with Debian, but perhaps there are official "groups" of packages that comprise a set of softwares, like KDE. Perhaps you could re-install that group, if it exists?
You could also create a new user, log in as that user, and see if the issue persists. If so then you'll know it's a system wide issue. If not, then maybe you could migrate to the new user?
Sadly I am not using BTRFS for my root directory on this specific system. If I end up deciding to reinstall, I will definitely go back to BTRFS to avoid such problems.
Debian actually has a KDE group named kde-full. I reinstalled it but the issue persists, which was honestly surprising to me.
~$ sudo apt install kde-full
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
kde-full is already the newest version (5:147).
0 upgraded, 0 newly installed, 0 to remove and 87 not upgraded.
The new user idea was really clever, thanks for the suggestion! I will try that now and see.
Edit: the new user also presents the same problem. Actually, it makes sense, since SDDM is affected as well (I should have mentioned that before).
Debian doesn't have package groups in that sense. kde-full is just a package which depends on the other KDE packages.
So, if you tell it to install kde-full, it'll just check that, yes, it does have the kde-full package installed, whether all the dependencies are fulfilled or not.
You can try doing apt --fix-broken install (without specifying a package), maybe that will pull in the missing dependency.
Or you can reinstall: apt reinstall kde-full
How did you install KDE in the first place? If you uninstalled too many packages for the logs to be of use, just reinstall KDE however you installed it
If I am not mistaken, I used a Debian KDE live image from the official repository then switched the mirrors from Bookworm to Sid. The system went months without a single issue, then this happen.
Your suggestion will actually be my solution of choice if everything else fails: reinstall / and import relevant files from a backup that I already have.
dont install the meta package unless you used it on install. It can cause shenanigans if you aren't careful, especially with application meta packages.
I did check it, yes, but the page doesn't appear to be relevant or contain much information. Another comment above (or below) mentioned that KDE Plasma can't run without a compositor.
That was actually my first attempt, but unfortunately I removed 484 packages during that process, so checking the log didn't help me much. Some packages that were removed had many dependencies that I could quickly recover, like Dolphin and Okular, but in the end I was left with ~100 packages that I don't know what they do.
While I could technically reinstall all of them manually, it would be less than ideal since many are indeed not needed and supposed to be removed during that update (apt complains about conflicts).
100 isn't that many really. If you're really curious I would try reinstalling them in steps of 10 to narrow it down. And when/if you identified the pack of 10 with the culprit, uninistall those 10 and install 1 by 1: max number of reinstalls/uninstalls = 20