Fix qt based tray icons not appearing on startup

[inv3rse]

The changes from #231 are delaying the registration of the StatusNotifierWatcher by ~2 seconds.
A lot of applications unfortunately do not wait for the dbus name to appear correctly.

The qt implementation with the QSystemTrayIcon, which is for example used in the Nextcloud app does not work correctly.
If during application startup it does not detect a StatusNotifierWatcher it does not wait for it show up.

The example project at https://doc.qt.io/qt-5/qtwidgets-desktop-systray-example.html has the same issue with the icon not appearing if launched on system start. (I removed the early isSystemTrayAvailable check, as nextcloud does not check for this either.)

It can also be reproduced by disabling this extension first and then launching the application.
Enabling the extension later will not trigger the indicator to show up.
It however works correctly if the extension is enabled during application start and then switched off and on again.

This pull request registers the watcher as soon as possible and only delays the visual indicator creation until the desktop startup completed.

Fixes #250

[flacks]

Initial tests have all my Qt icons appearing on login. Thank you very much so far; this has been an issue for me!

[ghost]

Tested, works for me.

[tbpoetke]

please merge ;)

[xen0m0rph2020]

Any updates?

[3v1n0]

Change looks good, will prepare a release soon

[P4Cu]

I got the same idea of the problem and indeed this pull fixes it. Just tested.

[rogercreagh]

So we are still waiting for it to be merged and then the next release - any idea of timescale when that is due?

[rmader]

Gentle ping about this on @3v1n0 :)

[felipe19930]

Guys calm down, this PR has been open for only 3 months now

[universam1]

any chance this fix be available? Other workarounds possible?

[sercxanto]

Same issue here with nextcloud client on ubuntu 20.04, but I think it affects other apps as well.

Also waiting desperately for a release of this bugfix ...

@universam1 not really a workaround, but downgrading gnome-shell-extension-appindicator to version 33-1 brings back the systray icon on my machine:

sudo apt install gnome-shell-extension-appindicator=33-1

You can prevent updates to the appindicator permanently, but I would not recommend it as you would also miss the update with the fix:

sudo apt-mark hold gnome-shell-extension-appindicator

[universam1]

but downgrading gnome-shell-extension-appindicator to version 33-1 brings back the systray icon on my machine:

That did the trick - thanks @sercxanto a lot for outlining this temporary workaround!

Still wondering why this fix is not rolling out? @3v1n0

[Dedas]

I have this exact issue with KeepassXC. The rollback fixed it. Would be nice with a real fix though.

[rmader]

FTR: I've been using this patch for three weeks now without encountering regressions.

[3v1n0]

Sorry, I took a while... I'll prepare the release once I'm done with some cleanups I've in mind

[3v1n0]

@inv3rse I've added some Promise's love in the code, so this change is now quite different and easy as per 46b757d, let me know if there's something I missed there :)

[JOduMonT]

Not sure but I have this issue with KDE Plasma: 5.18.8 on Ubuntu 20.04 LTS where Qt version is 5.12.8 I tried with the nextcloud-desktop version 2.6.2-1 and 3.4.4-20220318 from the PPA without a better result

[JOduMonT]

now I'm using Clear Linux with KDE 5.27.5 and Wayland
and flatpak to install flathub com.nextcloud.desktopclient.nextcloud and still have the same issue
the nextcloud client start, it show in task manager but when I minize it it simply disapear but still working in background

[anshah1216]

but downgrading gnome-shell-extension-appindicator to version 33-1 brings back the systray icon on my machine:

Thanks for your help @sercxanto.
I was having the QSystemTrayIcon disappear after reboot on both Ubuntu 20.04 and 22.04. The issue was fixed on Ubuntu 20.04 but on Ubuntu 22.04 I'm seeing that downgrade is not possible because gnome-shell-extension-appindicator 33-1 is not available.

$ sudo apt install gnome-shell-extension-appindicator=33-1
Package gnome-shell-extension-appindicator is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source
E: Version '33-1' for 'gnome-shell-extension-appindicator' was not found

Any ideas how to resolve this?