Sometimes GNOME Boxes (installed as flatpak on Fedora 30 Silverblue) window disappears from the shell. Don’t know why; I only know I did not close the window. In fact flatpak ps shows the process still running.
How can I restore the window?
If I start another window, I won’t be able to launch the box already running in the other process.
If I flatpak kill the process, I’ll have to restart again the box. I’d like to avoid this and understand what’s happening.
A fundamental issue we currently have in the Boxes Flatpak is that each instance of it has its own libvirtd daemon. This way, once you close Boxes (or it crashes), you loose access to that libvirtd process. Opening a new Boxes instance will spawn a new libvirtd in the sandbox, not reuse the one spawned in the previous container.
Besides, once you open a new instance of Boxes and try to connect to the VM you had opened before, libvirt will complain that there’s already a qemu-* process using that disk/image. That’s why flatpak kill “fixes” the issue. It kills all the processes in the first container and allows everything to start over again. That’s, of course, not an acceptable solution.
For this reason, I’m currently working on using the Flatpak “Background” portal to allow Boxes to run in the background when there are existing operations such as a VM you left running, a clone VM operation, etc… https://github.com/flatpak/xdg-desktop-portal/pull/319