I don't know if any of the Dev team has ever user the RemoteApp feature of remote desktop.
Its essentially virtual box's seamless mode for remote desktop. Instead of streaming an entire remote desktop it just streams the window of the app you are runnning.
I use remoteApp all the time. When I stream any app over remoteApp and processhacker is active in the background, its TrayIcon is streamed and shown as normal, but if I want to access processhacker, the tray icon cannot be interacted with. right and left click do nothing. hovering also doesn't spawn the mini info window.