> I think the solution to that should be something other than removing the sandbox. I see "portals" referred to elsewhere in this thread w.r.t. flatpak; does snap not have similarly?

Snaps use portals like flatpaks do. The problem is more about frameworks you build applications with not being ready to consume portals. Turns out only some reasonably recent Qt versions can work with portals. IIRC Electron only landed support couple of months ago. Back on the host side of confinement, you need to run a reasonably recent xdg-desktop-portal (and a maching GUI integration bit). Some old distros do not provide any of those packages or ship version that don't work, so things are DOA.