Distributing for Linux

Does anybody have a guide for preparing Xojo apps for distribution to Linux? It’s been a long while for me. My last adventure with the topic was building the rpm and deb installers for Xojo and Feedback. These days there seems to be more favorable options.

Flatpak seems like the most promising direction, but I can’t figure out what to tell it for a runtime. I’m not married to Flatpak either, so I’m open to other suggestions.

I package Linux apps as AppImages (for portability). A lot of the users of my Linux apps are on either Fedora or openSUSE so also build rpm’s for those.
I’ll try to find my latest notes on creating an AppImage for a Xojo app.

Desktop (GUI) or Server Process (Web, Console) ?

Desktop

This is the first I’m hearing of AppImage. Looking at Flatpak vs. Snap vs. AppImage | Side by Side Comparison suggests I’d probably want to look into Snap more though. AppImage has my curiosity, but it sounds like it wouldn’t handle setting up required dependencies such as libwebkitgtk.