STEPS TO REPRODUCE
1. open system tray settings
2. open an app with systray icon (I tested VLC, Juk player and Deluge torrent client)
app launched in the step 2 has no icon in "Entries" section of systray settings.
Close and reopen systray settings: now the app launched in the step 2 has an icon in "Entries" section.
apps with systray icon always have an icon in "Entries" section of systray settings.
Operating System: Arch Linux
KDE Plasma Version: 5.17.90
KDE Frameworks Version: 5.66.0
Qt Version: 5.14.0
The situation is a little bit better, but still the issue exists. You can scroll list down and up again, icon is rendered correctly.
I've done very limited investigation, but the problem is with rendering (ListView), model is updated correctly and changes are correctly notified.
I will investigate further.
Git commit 3ba955f4f5c50355976424984b49b3457f11d8f1 by Konrad Materka.
Committed on 26/01/2020 at 22:18.
Pushed by kmaterka into branch 'Plasma/5.18'.
[SystemTray] Fix model update in settings (missing icon)
Fixes a bug, when system tray settings is opened and new application is opened, view is not correctly refreshed and icon is missing. Caused by duplicated role names. Related to: D26586
1. Open system tray settings
2. Open an app with systray icon
Icon, title etc are correctly rendered.
Reviewers: #plasma_workspaces, #plasma, davidedmundson, ngraham, broulik
Reviewed By: #plasma_workspaces, #plasma, davidedmundson
Differential Revision: https://phabricator.kde.org/D26850
M +9 -1 applets/systemtray/systemtraymodel.cpp