Linux Client, behaviour with multiple Monitors

[DavidJ47]

Ubuntu "sort of" works with two Monitors attatched (sort of because there seems to be some issues still, regarding the way the monitors are location wise)
Manjaro however simply does not work with two Monitors. It always only uses one screen for the remote connection

The most peculiar thing is, both use the exact same Version of Gnome, both of these use pretty much the same Hardware (i personally am a lot more familiar with Manjaro, while my colleque is more familiar with Ubuntu), same "standard" Linux Kernel, both are in XORG Mode and do not use Wayland.

Is there any setting i can change? I've experimented with the Client Settings for multiple Monitors (Desktop on all Monitors and so on), but nothing changed. The Manjaro client will not use both Monitors for the RAS Desktop.

I would like to avoid reinstalling the Manjaro one, because those have become personal devices for the users in question...

 

[jpc]

Multi monitor usage can be:
* disabled in the client-side setting for published apps ("Display" > "use primary monitor only")
* disabled by having client-side setting "span desktop across all monitors" (it will try to span but declare a single monitor), but you have tried that already
* forced or disabled on the server-side for published desktops: "Publishing" > <app> > "Desktop" > "Desktop Size" = Full screen, "enable" (multi monitor forced) or "disable" (single monitor forced).
* for standard RDP connections, there is obviously the client-side option to use "fullscreen" ("Display" > "Size" and to "Use all monitors for Desktop session (if applicable)", where if applicable just means if the size is set to fullscreen).

As far as RDP itself goes, there are gpos to restrict the number of monitors that can be redirected via RDP (although they are not commonly used nowadays) and, particularly size limitations per-monitor/total-display depending on the RDP server one is connecting to.