Comment 1 for bug 2065088

Installing from Valve's official steam-launcher .deb package runs into the same problem. The same workaround works.

1. Boot an Ubuntu 24.04 live image, in a virtual machine with lots of RAM (I gave it 8G) so that it will have enough space on the root tmpfs to install Steam. Using Debian 12's libvirt and qemu, I found that virtio graphics didn't work, and used qxl as a workaround.
2. When prompted, choose a keyboard layout etc., and choose to "Try Ubuntu" rather than "Install Ubuntu".
3. Open a terminal
5. sudo apt update
4. Copy steam_latest.deb or steam-launcher_*.deb onto the machine somehow: in this test I was evaluating a new release that is not yet public, but I expect the same thing would happen with Valve's official .deb.
6. sudo apt install ./*.deb
7. steam
8. See a light grey progress bar "Steam setup / Updating Steam runtime environment...". Wait.
9. See a dark grey progress bar "Steam / Updating Steam... Downloading update (xxx of 465,450 KB)...". Wait.
10. Dark grey progress bar becomes "Steam / Updating Steam... Extracting package...". Wait.
11. Output in terminal shows "Restarting Steam by request...". Wait.

Expected result: same as in initial report

Actual result: same as in initial report