I resolved the dbus issue via flatpak permissions.

Now, I can't get my software to check as reliable.

I have successfully completed the procedure several times, but it still displays this message.
the logs
flatpak run im.riot.Riot
LaunchProcess: failed to execvp:
xdg-settings
LaunchProcess: failed to execvp:
xdg-settings
/home/julien/.var/app/im.riot.Riot/config/Element exists: yes
/home/julien/.var/app/im.riot.Riot/config/Riot exists: no
(node:3) [DEP0180] DeprecationWarning: fs.Stats constructor is deprecated.
(Use `element-desktop --trace-deprecation ...` to show where the warning was created)
Loading app config: /app/Element/resources/webapp.asar/config.json
Loading local config: /home/julien/.var/app/im.riot.Riot/config/Element/config.json
Skipping nonexistent file: /home/julien/.var/app/im.riot.Riot/config/Element/config.json
Reached Electron ready state
Auto update not supported on this platform
Fetching translation json for locale: en_EN
Changing application language to fr
Fetching translation json for locale: fr
Resetting the UI components after locale change
Resetting the UI components after locale change
Opening main window
Ensuring storage is ready
Using storage mode 'encrypted' with backend 'kwallet6'
(node:3) [DEP0044] DeprecationWarning: The `util.isArray` API is deprecated. Please use `Array.isArray()` instead.
Reading setting value for: Electron.warnBeforeExit = true
Reading setting value for: Electron.alwaysShowMenuBar = false
Reading setting value for: Electron.showTrayIcon = true
Reading setting value for: Electron.enableHardwareAcceleration = true
Changing application language to fr
Fetching translation json for locale: fr
Resetting the UI components after locale change
Reading setting value for: Electron.autoLaunch = disabled