The older version 4.29.149 works fine. I found the following error in the logs:
[2:0501/151013.326793:ERROR:bus.cc(562)] Failed to get the ownership of org.kde.StatusNotifierItem-2-1: org.freedesktop.DBus.Error.ServiceUnknown
Via Flatseal I gave Slack access to dbus, but the error persisted in logs and the tray icon did not appear again. Current workaround is to rollback to version 4.29.149
The older version 4.29.149 works fine. I found the following error in the logs:
Via Flatseal I gave Slack access to dbus, but the error persisted in logs and the tray icon did not appear again. Current workaround is to rollback to version 4.29.149