The Problem
After upgrading to Fedora 44, Electron-based flatpaks (Slack, Signal, Spotify, Mattermost, Telegram, Jitsi, Bruno, Bitwarden, Discord, Postman, Element) and other apps (Flatseal, Flameshot, DBeaver, Zed) stopped working with errors like:
[4:0521/150051.341274:ERROR:ui/ozone/platform/wayland/host/wayland_connection.cc:202]
Failed to connect to Wayland display: Connection refused (111)
[4:0521/150051.341335:ERROR:ui/ozone/platform/wayland/ozone_platform_wayland.cc:281]
Failed to initialize Wayland platform
[4:0521/150051.341428:ERROR:ui/aura/env.cc:246]
The platform failed to initialize. Exiting.
The apps try Wayland, fail, then don’t fall back to X11.
Users running XFCE (or any X11 session) under GDM are especially affected
because GDM reports XDG_SESSION_TYPE=wayland even for X11 sessions, which
confuses Electron/Chromium auto-detection.