Qubes OS 4.3.0 - Settings tab disappears when selecting a device in "boot from existing block device" option

almost_crazed · January 14, 2026, 6:07pm

hello,

I’m experiencing an issue while using the “From existing block device” method in Qubes OS 4.3.0. When I select the specific device I want to boot from, the settings tab disappears without any error message or explanation. The qube can be started using the ‘Start the qube’ option; however, I receive the message ‘No bootable device found.’

Thank you very much.

Atrate · January 14, 2026, 7:53pm

Are you using a custom theme for the Qube manager (such as Adwaita-dark)?

Atrate · January 14, 2026, 7:58pm

In general, it sounds like a crash. Run qubes-qube-manager from a dom0 terminal, run sudo journalctl -f in another dom0 terminal and see if any errors pop up when the tab disappears.

almost_crazed · January 15, 2026, 8:43am

No, I’m not using any custom theme. However I did add two additional software package Desktop accessibility and Sway Window Manager (supplemental packages) alongside Qubes UI (Audio/GUI) during the installation.

ben-grande · January 15, 2026, 9:15am

Can you please run the commands instructed here an report, so it can be fixed?

almost_crazed · January 15, 2026, 10:02am

It says “dom0 qubesd[XXXX] : WARNING: protecol error for call b’admin.vm.device.block.Assign’+b’sys-usb+sda’ (b ’ dom0’ → b ’ the VM’s name ’ ) with payload of 286 bytes”
It does not matter what partion I select the paylaod stays the 286 bytes in every error

Immediately after that I receive this error “dom0 qubes-app-menu[XXXX] : Error : Got empty response from qubesd. See journalctl in dom0 for details.”

ben-grande · January 15, 2026, 11:17am

might be related

github.com/qubesos/qubes-issues

"Boot qube from DISK or block device" in Qube Settings doesn't work in 4.3

opened 10:31AM - 19 Aug 25 UTC

faklapant23

C: Qubes GUI tools P: default needs diagnosis affects-4.3

[How to file a helpful issue](https://www.qubes-os.org/doc/issue-tracking/) ###… Qubes OS release R4.3 rc1 ### Brief summary "Boot qube from DISK or block device" in Qube Settings doesn't work Qubes OS 4.3 (clean install, dom0 updated to the latest testing updates). Booting with ISO work fine from dom0 terminal using qvm-start with ISO from exposed loop device, so it's a problem with GUI. ### Steps to reproduce Try to boot from ISO in a standalone qube not based on a template using Qube Settings GUI. The ISO is stored in the app qube based on a default debian-12-xfce template with latest updates. When you go to the standalone qube's Qube Settings -> Advanced -> press on "Boot qube from DISK or block device" -> from file in qube -> select the qube and press a ... button -> it'll open a file selection dialog and you choose the ISO from this qube. After confirming the chosen file, it'll display a window with this error: ``` [Dom0] Failed to display file selection dialog Check if the qube storage can be started and has a file manager installed. ``` The same problem happens when using different ISOs. Another issue is with booting "from existing block device". Created loopback device with ISO in the qube: ``` sudo losetup -f /path/to/iso ``` Then try to boot it from the GUI, but choosing "from existing block device" instead of "from file in qube" this time. It doesn't work as well. After choosing block device and pressing OK, the Qube Settings closes, but the qube with this image doesn't start. ### Expected behavior It's possible to boot a standalone qube not based on a template with ISO using GUI. ### Actual behavior Both booting "from existing block device" and "from file in qube" in GUI don't work. ### Additional information

almost_crazed · January 15, 2026, 4:06pm

Thank you.