I have Microsoft Outlook sandboxed, and I would prefer not to have its tray icon cluttering up my system tray, but MS doesn't provide any setting to disable the tray icon. In issue #4684, a user found that adding OpenWinClass=* to the sandbox config made sandboxed tray icons disappear. This works on my Outlook sandbox.

However, that is a dangerous config that opens up much more of the system than I'd prefer, so I tried to narrow it down. I traced the different win classes that were called and tried opening all of them, like this:

OpenWinClass=MsoCommandBarPopup
OpenWinClass=MsoWorkPane
OpenWinClass=MSTaskSwWClass
OpenWinClass=Net UI Tool Window
OpenWinClass=NetUICtrlNotifySink
OpenWinClass=NetUIHWND
OpenWinClass=NetUINativeHWNDHost
OpenWinClass=NUIPane
OpenWinClass=OfficeTooltip
OpenWinClass=OUTLOOK.EXE-48a4-0010000048bf4ed2-PCacheWindow
OpenWinClass=Progman
OpenWinClass=REListbox20W
OpenWinClass=Sandbox:FireBox:Chrome_WidgetWin_1
OpenWinClass=Shell_TrayWnd
OpenWinClass=WMS Notif Engine:Dispatch Window Class
OpenWinClass=WMS ST Notif Class

That didn't work. So I tried opening wnd classes for all the programs SBIE says are running in that sandbox, like this:

OpenWinClass=OUTLOOK.exe,*
OpenWinClass=ai.exe,*
OpenWinClass=SandboxieRpcSs.exe,*
OpenWinClass=SandboxieDcomLaunch.exe.exe,*
OpenWinClass=SandboxieCrypto.exe.exe,*

That didn't work either.

So, I'm missing whatever it is specifically that blocks the tray icon. Does anybody have an idea what might do it?