[Post-Install] After a system update within 26.04 Steam refuses to run even after commands for namespace

[MichaelEber]

As soon as it was available i installed Kubuntu 26.04. I have had everything working without any issues, including running Steam. A day or two ago I had an update that I ran and at the end of the update it stated I had to restart in order to complete the install. I must assume that meant some operating system files had to be dealt with in that update and I restarted my system. After that, the next day I noticed I didn't have Steam running so I started it and got an error:

Steam now reqwuires user namespaces to be enabled.

This requirement is the same as for Flatpak, which has more detailed information available:
https://github.com/flatpak/flatpak/w...e-requirements.

First I tried to make send of that and got lost. So I googled how to do this and followed the directions.

FIRST:
echo 'kernel.unprivileged_userns_clone=1' | sudo tee /etc/sysctl.d/10-user-namespaces.conf sudo sysctl -p /etc/sysctl.d/10-user-namespaces.conf

after which I did this:
If you are on Ubuntu 24.04, you may also need to disable AppArmor restrictions by creating /etc/sysctl.d/60-apparmor-namespace.conf with the content kernel.apparmor_restrict_unprivileged_userns=0, then applying it via sudo sysctl -p /etc/sysctl.d/60-apparmor-namespace.conf.

Then I finally tried the last step:
sudo setcap -r $(which bwrap) It stated that ther is no remove command
sudo chmod u+s $(which bwrap) Seemed to run without a problm

After all of this I went to launch Steam and it flushed itself down the toilet once again!!! HELP

[claydoh]

Can you tell us which package type you used to install Steam? Snap, flatpk, or deb?
You should be able to tell by looking for it in Discover.


and before people chime in on snap/flatpak , this problem seems to have occurred in all the different types, even on Arch. at different times. Proton itself uses namespaces for sandboxing, unrelated to snap or flatpak, though it uses the same tools for it (bwrap) that at least flatpak does.

I think these older reports from the btw crowd and the cachy-crazed clog the search results, and thus also the LLM tools.


......and having said that, I am going to guess it is the Snap:

https://github.com/canonical/steam-snap/issues/519

Which probably should be remedied shortly if not already done:
https://forum.snapcraft.io/t/autocon...-steam/52098/3

To fix it now, assuming Snap:

snap connect steam:mount-observe​

For Steam odditities, I generally look for very recent Steam forums and github issues first.
https://steamcommunity.com/app/22141...64991158544526