I'm getting this from bash: echo $XDG_DATA_DIRS /usr/share//usr/share/xsessions/plasma:/usr/local/share/:/usr/share/:/var/lib/snapd/desktop I believe there is a ':' missing? Reproducible: Always Steps to Reproduce: 1. A program that pointed me to investigate XDG_DATA_DIRS was Nylas e-mail client. it fails to get system tray icon at the moment. But I'm not sure it's because of this... 2. after installation, add any mail account and be sure to enable system tray icon on preferences, if something did not show on system tray. Actual Results: missing icon for system tray, fall to default "no icon". It may be affecting the software Icon too as it differs, the panel from the one on app windows. Expected Results: Nylas Icon on sys. tray.
> DESKTOP_SESSION=/usr/share/xsessions/plasma which will be prepended to the variable by a core x11 setup script > $ grep -r SESSION\": /etc/X11/Xsession.d/60x11-common_xdg_path > XDG_CONFIG_DIRS="$DEFAULT_XDG_CONFIG_DIRS"/xdg-"$DESKTOP_SESSION":"$XDG_CONFIG_DIRS" > XDG_DATA_DIRS=/usr/share/"$DESKTOP_SESSION":"$XDG_DATA_DIRS" So I am guessing that every DM other than SDDM actually treats DESKTOP_SESSION as the basename (excluding suffix) of the xsession file name. Please forward this bug to SDDM on github. As for your actual problem of icons not working. This probably has nothing to do with it since /usr/share//usr/share/xsessions/plasma == /usr/share/usr/share/xsessions/plasma which is a valid path, and the XDG spec doesn't mandate that the paths in the variable exist at all, so even though it is malformed it shouldn't matter. That said, depending on how Nylas renders the systray icons and whether it has own icon lookup code involved it is entirely possible that the lookup code is incorrect and breaks on non-existant paths in XDG_DATA_DIRS. I suggest you file a bug report with the Nylas authors as they are probably in a better position to guess where the problem might be.
I encountered this bug, and did some investigation. * The core X11 setup script (60x11-common_xdg_path) was created by Ubuntu: https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/804734 * There is a recent bug report about this very issue on Launchpad: https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1668722 I have filed a bug with SDDM on Github: https://github.com/sddm/sddm/issues/852 I feel Ubuntu could improve its script, too. Anyway, this is all outside of the scope of Neon.