The Wrong Terminal

Somewhere in my Pop!_OS 22.04 settings, I set Tilix as the preferred terminal emulator. When I use the Super+T* keyboard shortcut, I get a Tilix window.  However, when I use a launcher that Distrobox has created for a container from the Super+A (for Applications) UI, the command-line doesn’t come up in Tilix… it comes up in gnome-terminal instead. Why is that, and can I fix it?

AIUI, all the Application Launcher UI does is ask the system to open the .desktop file that Distrobox added.  That file has the “run in terminal” option, but lacks the ability to request some specific terminal. That gets chosen, eventually, by the GIO library.

GIO isn’t desktop-specific, so it doesn’t read the desktop settings.  It actually builds in a hard-coded list of terminals that it knows how to work with, like gnome-terminal, konsole, and eventually (I am assuming) ye olde xterm.  It walks down the list and runs the first one that exists on the system, which happens to be gnome-terminal.  AFAIK, there is no configuration for this, at any level.

It is also possible that one of the distributions in the chain (Debian, Ubuntu, or Pop!_OS) patched GIO to try x-terminal-emulator first.  If so, it would go through the alternatives system, which would send it directly to gnome-terminal, since between that and Tilix, gnome-terminal has priority.  We are deep into speculative territory, but if all of that were the case, I could “make it work” by making a system-level change resulting in all users now preferring Tilix… but only for cases where x-terminal-emulator is involved, specifically.

I want the admin user to have all the defaults, like gnome-terminal, because the less deviation made in that account, the less likely I am to configure a weird problem for myself.** (Especially for Gnome, which has a configuration system, but they don’t want anyone to use it.  For simplicity.) Changing the alternatives globally is in direct contradiction to that goal.

It seems that the “simplest” solution is to change the .desktop file to avoid launching in a terminal, and then update the command to include the desired terminal.  It would work in the short term, but fall “out of sync” if I ever changed away from Tilix as default in the desktop settings, or uninstalled Tilix.  It’s not robust.

It seems like there’s some sort of desktop-environment standard missing here.  If we don’t want to invoke threads or communication inside GIO, then there would need to be a way for the Gnome libraries to pass an “XDG Configuration” or something, to allow settings like “current terminal app” to be passed in.

If we relax the constraints, then a D-Bus call would be reasonable… but in that case, maybe GIO could be removed from the sequence entirely.  The Applications UI would make the D-Bus call to “launch the thing,” and a desktop-specific implementation would pick it up and do it properly.

It seems like there should be solutions, but from searching the web, it looks like the UX has “just done that” for years.

* Super is the |□| key, because it's a System76 laptop, a Darter Pro 8 in particular.

** As a side effect, this makes the admin account feel like “someone else’s computer,” which makes me take more care with it.  I may not want to break my own things, exactly, but I would feel even worse about breaking other people’s stuff.