Any way I can fake an update to check if the Zenity popup is failing? I definitely haven't seen one in the past.

I might be suffering from the same issue. If I check for updates in standalone mode (gamescope launched from sddm) it gives me an update error and I'm unable to launch games. Enter desktop mode and the update check proceeds as normal (no updates detected) and games launch as normal

I don't think that's quite what I'm experiencing. For me the updates do work, they just take a really long time (because of my internet connection) and there's no indication (unless launched from terminal) that anything is happening while the update proceeds.

Just as a sanity check, I can manually create a Zenity popup with a progress bar, assuming that is what the steam client uses as I haven't ever actually seen it.

My issue was fixed silently. It was probably the backend SteamOS changes they made recently.

I think I'm running into this issue as well, only it's occurring when launching Steam for the first time on the Kubuntu 26.04 development release. Just install a system using https://cdimage.ubuntu.com/kubuntu/daily-live/pending/, download and install the steam_latest.deb file, launch Steam, and proceed through the confirmation prompts. Eventually all the prompts will close, and you'll be left looking at a blank desktop. If you run sudo journalctl --boot and scroll to the bottom, you'll see the updater progress (apparently it gets logged to the systemd journal), and Steam will eventually show its login window, but it takes a long time for that to happen with my connection speed.

Same issue here on Ubuntu 26.04. It looks like the installer process is forking a new process to continue the installation, and the original process exits which is piping to Zenity is closing. I have verified some aspects of this by logging steam processes in a crude fashion:

true > report.log
while true; do
  ps -elf |grep -i steam >> report.log;
  sleep 0.1;
  echo '==== tick 0.1s ====' >> report.log;
done

# And in another window, run:
rm -rf ~/.steam*;
steam;

The Zenity window with the progress bar is run for 0.3s.

You can simulate how this works like so:

for (( idx=0; idx+=10; idx<101)); do echo "${idx}"; sleep 1; done \
  | zenity --progress --auto-close --percentage 0 \
      --title='Setup' --text='Updating stuff';

I have identified that the process ubuntu12_32/steam-runtime/setup.sh process is likely the one that pipes to the zenity progress bar. Not only does it start immediately before the zenity process, it also ends right after the last call to zenity before that process is terminated. It then appears that debian-installation/steam.sh continues the installation, but that's just a guess.

I hope that is useful!

Hi Steam Team, any word on this? I suspect this is a duplicate of others.

Just got a popup for part of the update process, it was titled "Unpacking steam runtime" or something like that. As usual the update took long enough that I wasn't sure it was still proceeding.