The general problem with LXQt is that its notification system will spam extra instances of `/usr/bin/lxqt-config-monitor -l` whenever there is a new notification. These instances cannot be closed and with lxqt-base/lxqt-notificationd-1.1.0 the "tray" widget is replaced with "statusnotifier" widget. The solution to this problem with "tray" was that you had a notification area which you can click and dismiss notifications, thus closing hanging instances of the lxqt-config-monitor process. With "statusnotifier", this notification area is invisible and unclickable, and thus a system that generates a lot of notification can quickly run out of open file handles. Each instance of lxqt-config-monitor opens a few file handles. Reproducible: Always Steps to Reproduce: 1. Generate a lot of notifications during LXQt session. For me, notifications happen every time I switch out of my computer with a KVM switch. 2. Your programs mysteriously stop starting because you exhaust open file handles over the course of a 1-3 week uptime. Actual Results: I ran out of file handles after 1-3 weeks of uptime and was surprised why I can't open connections in Python requests, why I can't open tabs in Firefox, and I was left scratching my head why is my desktop so badly crippled for no reason. Expected Results: Ideally lxqt-config-monitor should stop doing such a silly thing like depleting file handles, but if this is not possible, then "statusnotifier" should provide a clickable notification area.
I just started gcdemu and it's not showing up in the system tray. I don't think statusnotifier is a mature replacement for tray. I added tray back and gcdemu, networkmanager and notificationd are suddenly there.
This sounds like an issue which should be reported upstream to lxqt.
Thw 'statusnotifier' plug-in has been the default over 'tray' for some time, at least since 0.17.1 for us but I believe upstream deprecated it already before that. I've only kept it around at all because some applications don't make use of the new stuff (mostly probably GTK+-2 applications such as claws-mail). I think LXQt added some workaround for that too, so that they could now make use of 'statusnotifier' as well, but I never looked into it deeper. In any case, I tested the notifications a little by disabling 'tray' and leaving only 'statusnotifier' around, and I did get the notification thingy show up for screenshots when saving them using Screengrab. I also didn't notice instances of 'lxqt-config-monitor -l' show up. That seems little like the screen settings somehow changed, because I remember seeing a notification every time I launched LXQt without some settings saved manually (the notification would say something like "default monitor settings have been applied". Have you tried using fresh and clean user profiles to test if it isn't some issue with the configuration files?
I adjusted this to be about the KVM switch issue, as this seems to be more about that. Not that I know what we could do about it, aside from see if upstream can find a fix for it. I'll leave this open for now to track that. The system tray/statusnotifier is a different issue, and basically comes down to the GTK applications needing changes on that front (I just tested gcdemu as well, and indeed, it would not show up on the statusnotifier widget, but only on the tray one).
The issue persists on LXQt 2.0.0 unfortunately