I've looked everywhere and nobody seems to have complained about this at all. My original problem is that Clementine built with qt5's system tray icon is grouped with the hidden icons. Using the qt5 example systray this also happens. Clementine built with qt4 doesn't have this problem. I don't know if this is a plasma bug or if there's a trick with qt to make the icon fully visible. KDE sytem tray items don't have this problem, I've tried to see how kdeconnect manages it but I can see no clues. It happily becomes visible when I run kdeconnect on my phone.
Can a non kde qt5 app present a visible system tray icon?
https://doc.qt.io/qt-5/qtwidgets-deskto ... ample.html

I also have this probleme

I also have this problem and want to raise this question again and bring it to the attention of somebody who could help. There must be a way to do this, as e.g. the device manager or the software update plasmoid are quite able to control whether their tray icon is directly visible or only displayed when clicking the up arrow.

Up to now I have only found that you can configure the visibility of the tray icon by changing the visibility notification settings from "automatic" to "always". But what is then automatic? How can this be triggered programmatically?

It seems that the "automatic" option has something to do with notifications, at least I found this very old post going in this direction: viewtopic.php?f=93&t=92998. But I do not have a clue how this interacts and what I could do in my application to control the visibility of the tray icon.

This is probably something to ask the Plasma developers.

I wouldn't be surprised if there was an actual API for Systray icons that needs to be respected by the application, but I am not a dev. Please be patient as it is Friday evening now here, so this might take a while.

The answer was fast, I suggest you people update your Plasma versions: https://cgit.kde.org/plasma-integration ... 849ab04380