All hosts on arch linux. Connecting to xrdp from guacamole by rdp shows all AltGr keys are working except ~ (tilde). I am using firefox as browser.
Connecting with rdesktop to xrdp shows ALL keys working, including ~ (tilde).
So the problem is definitely related with guacamole in some way.
All boxes configured to german and server-layout set to de-de-qwertz.
When pressing "~" a "\ " is shown (backslash space).