Issues installing KDE on CentOS 9 Stream

[ngrusz1]

I am building a new system and would like to run CentOS 9 Stream with KDE Plasma. There are a handful of tutorials on the web detailing how to install the necessary packages and switch from Gnome to KDE; the best representation of these tutorials is probably the one at LinuxCapable.com.

All of the tutorials boil down to enabling a few repos and then using dnf to install the "KDE Plasma Workspaces" group of packages. I have a fresh install of CentOS 9 and I just cannot get this to work.

All of the necessary packages are supposedly available in EPEL. With just the EPEL repo enabled, I get the following errors when I attempt to install the packages:

Code: Select all

[user@localhost ~]$ sudo dnf groupinstall "KDE Plasma Workspaces" -y
Last metadata expiration check: 0:16:58 ago on Tue 12 Jul 2022 09:16:53 PM CDT.
No match for group package "k3b-extras-freeworld"
No match for group package "gstreamer1-plugins-ugly"
No match for group package "gstreamer1-plugins-bad-freeworld"
Error: 
 Problem 1: package qt5-qtwebengine-5.15.8-3.el9.1.x86_64 requires libQt5Gui.so.5(Qt_5.15.2_PRIVATE_API)(64bit), but none of the providers can be installed
  - package qt5-qtwebengine-5.15.8-3.el9.1.x86_64 requires libQt5Widgets.so.5(Qt_5.15.2_PRIVATE_API)(64bit), but none of the providers can be installed
  - cannot install both qt5-qtbase-gui-5.15.2-26.el9.x86_64 and qt5-qtbase-gui-5.15.3-1.el9.x86_64
  - cannot install both qt5-qtbase-gui-5.15.2-27.el9.x86_64 and qt5-qtbase-gui-5.15.3-1.el9.x86_64
  - cannot install both qt5-qtbase-gui-5.15.2-28.el9.x86_64 and qt5-qtbase-gui-5.15.3-1.el9.x86_64
  - cannot install both qt5-qtbase-gui-5.15.2-29.el9.x86_64 and qt5-qtbase-gui-5.15.3-1.el9.x86_64
  - package kdeplasma-addons-5.23.5-2.el9.x86_64 requires libQt5WebEngineCore.so.5()(64bit), but none of the providers can be installed
  - package kdeplasma-addons-5.23.5-2.el9.x86_64 requires libQt5WebEngineCore.so.5(Qt_5)(64bit), but none of the providers can be installed
  - package kdeplasma-addons-5.23.5-2.el9.x86_64 requires libQt5WebEngine.so.5()(64bit), but none of the providers can be installed
  - package kdeplasma-addons-5.23.5-2.el9.x86_64 requires libQt5WebEngine.so.5(Qt_5)(64bit), but none of the providers can be installed
  - cannot install the best candidate for the job
  - conflicting requests
 Problem 2: package qt5-qtwebengine-5.15.8-3.el9.1.x86_64 requires libQt5Quick.so.5(Qt_5.15.2_PRIVATE_API)(64bit), but none of the providers can be installed
  - cannot install both qt5-qtdeclarative-5.15.2-10.el9.x86_64 and qt5-qtdeclarative-5.15.3-1.el9.x86_64
  - cannot install both qt5-qtdeclarative-5.15.2-9.el9.x86_64 and qt5-qtdeclarative-5.15.3-1.el9.x86_64
  - package kmail-21.08.3-1.el9.x86_64 requires libQt5WebEngineCore.so.5()(64bit), but none of the providers can be installed
  - package kmail-21.08.3-1.el9.x86_64 requires libQt5WebEngineCore.so.5(Qt_5)(64bit), but none of the providers can be installed
  - cannot install the best candidate for the job
  - conflicting requests
(try to add '--allowerasing' to command line to replace conflicting packages or '--skip-broken' to skip uninstallable packages or '--nobest' to use not only best candidate packages)

Some tutorials include instructions to enable the EPEL-Next repo. Unfortunately this still doesn't work. With the EPEL-Next repo enabled, I get this error:

Code: Select all

[user@localhost ~]$ sudo dnf groupinstall "KDE Plasma Workspaces" -y
Last metadata expiration check: 0:00:01 ago on Tue 12 Jul 2022 09:35:57 PM CDT.
No match for group package "k3b-extras-freeworld"
No match for group package "gstreamer1-plugins-ugly"
No match for group package "gstreamer1-plugins-bad-freeworld"
Error: 
 Problem: cannot install the best candidate for the job
  - nothing provides egl-utils needed by kinfocenter-5.24.5-2.el9.next.x86_64
(try to add '--skip-broken' to skip uninstallable packages or '--nobest' to use not only best candidate packages)

I haven't tried to use the --nobest or --skip-broken options yet, and I'd really prefer not to. With a fresh install, it would be nice to have everything working properly with all the necessary packages to start out. None of the tutorials or other posts describing how to install KDE discuss issues like this.

Does anyone have any thoughts on what the problem might be? Perhaps the repo developers are simply in between package rollouts and it's just dumb luck that I happen to be trying to install KDE right now (and after a week or two the problem will fix itself)?

[ngrusz1]

Unfortunately it appears the solution here is to switch to AlmaLinux. I started over and installed a fresh copy of AlmaLinux. I used the dnf groupinstall "KDE Plasma Workspaces" command right after install (just like I tried with CentOS 9 Stream) and this time it seems to have worked as intended. KDE installed successfully and I was able to log in using it. I would guess it would be similarly successful with Rocky Linux as well.

So...not sure why it doesn't work with CentOS 9 Stream, which is disappointing. Unfortunately perhaps this highlights a real-world difference between the CentOS 9 Stream and what would have been the traditional version of CentOS 9 before The Change?

In any event, it looks like if you'd like to use KDE with EPEL packages, you'll have better luck with something like Alma or Rocky.

[jlehtone]

perhaps this highlights a real-world difference between the CentOS 9 Stream and what would have been the traditional version of CentOS 9 before The Change?

Quite likely.

The RHEL 8.6 did(/does?) have an issue too involving kernel, qt5, sddm, and KDE, so the combo is not trivial and since Red Hat only keeps RHEL consistent, that leaves third-party providers on slippery ice. That issue is probably not in 9 as it is due to backport to 8's kernel, but if kernel-KDE pairing is tricky, the fact that Stream has different kernel than RHEL will certainly not make things easier.