KDE Neon (Noble) Update Failing: Unmet dependency for kf6-kfilemetadata (libpoppler 24.08.0)

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1

Hey everyone,

I’m running a fresh install of KDE Neon (based on Ubuntu 24.04 Noble) from a late February ISO. When attempting to run standard system updates via pkcon refresh && pkcon update today, it hard-fails with unmet dependencies.

It looks like the newest kf6-kfilemetadata package pushed to the repo requires a newer version of libpoppler than what is currently available in the Noble base.

Here is the exact fatal error from pkcon:
Fatal error: The following packages have unmet dependencies: kf6-kfilemetadata: Depends: libpoppler-qt6-3t64 (>= 24.08.0) but 24.02.0-1ubuntu9.8 is to be installed

Running apt full-upgrade --dry-run confirms the exact same roadblock, with apt wanting to hold back a massive chunk of Plasma 6 (plasma-desktop, plasma-workspace, dolphin, ark, etc.) because it can’t resolve the libpoppler-qt6-3t64 mismatch.

It seems the build server might have missed pushing the backported 24.08.0 libpoppler package to the user mirror alongside the new Frameworks update.

Just wanted to give a heads-up so the build server can get kicked! Let me know if you need any more logs.

2

I saw this on my daily update, but my system is up-to-date so only libpoppler-qt6-3t64 was held.

Apt gives better information here for troubleshooting, but in the end, try this to install the correct version of libpoppler-qt6:

sudo apt update (if you haven't already)
sudo apt install libpoppler-qt6-3t64=24.08.0-1+24.04+noble+release+build15

Hopefully this allows all the updates to install, I only had issue with a single package since I already had all the Plasma 6.6.3 updates, and had only three other non-KDE updates that installed just fine, other than this one.

However, subsequent updates want to revert back to the old package version, so I suspect some apt pinning configuration collisions are happening.

3

Ok, maybe a fix:

If one edits the file /etc/apt/preferences.d/99-noble-overrides and comments out the 3 lines referring to libpoppler-qt6-3t64 (lines 1221-1223 for me), and try updating again, things did work.

4

I do not know if this edit is the best way to go long term, as I still don’t fully understand what is going on in the preferences file, so do use this at your own risk.

5

got me back in business, thanks!

6

thanks, from me. Now Working again

7

This is fixed in the current update batch.

8

Today I got kicked out of Plasma. Neon made some updates, screenlocker stopped working and after reboot I could not login to graphical Plasma desktop.

It seems, that the system was not able to install that same libpoppler-qt6-3t64, liblcms2-2 and libeisl1 because of higher pin-priority on lower Ubuntu versions. Those libraries were blocking kwin-common and kwin-wayland.

I commented lines for those libraries in /etc/apt/preferences.d/99-noble-overrides and after that sudo pkcon refresh and sudo pkcon update started a big upgrade.

Let’s see, if that fixes my system.

9

Yes! The update finished fine and as a reward I got Plasma 6.6.