Starting Tixati with systray icon enabled, or toggling systray icon enabled, produces the error:
Gtk-CRITICAL **: gtk_widget_get_scale_factor: assertion 'GTK_IS_WIDGET (widget)' failed
No change with libappindicator installed, display scaling disabled, or resetting various Plasma config files to defaults. plasma-xembedsniproxy.service is running. No other apps are missing systray icons. Another computer configured similarly but using Xorg does show a Tixati systray icon.
, other users in 2022 had Tixati systray icons on Plasma + Wayland, but they were dysfunctional. Not sure if this means my having no icon points to a local config problem, or if it's something that broke since last year.