OwnCloud Client not visible using xrdp to connect to Raspberry Pi

I’m running OwnCloud Client 2.2.4 on a Raspberry Pi running Raspbian Stretch. All works fine but …

When I connect to the Pi from a Windows client using Windows Remote Desktop (the Pi is running xrdp v0.1.9-9) the OwnCLoud Client is not visible on the Remote Desktop! Neither the displayed client GUI nor the Notification Tray icon appear. I can do pretty much everything on the Pi using the remote desktop EXCEPT manage the OwnCloud client. I’m thinking this is an issue with the X-server display not being properly “exported” to/through the remote desktop display.

Any suggestions?

Did you have a look at this? Maybe a similar problem?

Thanks for the suggestion, but I don’t think that’s the issue. The client starts and works just as expected when I’m sitting at the Pi with a display and keyboard connected. But even when I know the client is running, if I connect to the Pi using the Remote Desktop Protocol from a Windows host, the OwnCloud client is simply “invisible.” OwnCloud DOES get listed in Task Manager and with the “ps -A” command. But there’s no GUI on the Remote Desktop display.
As I indicated in my post, I believe it’s related to the X-session that OwnCloud is using being different from the session that is being “exported” to the Remote Desktop. So, I guess this may not technically be an OwnCloud issue per-se. But it’s maddening, and any help would be appreciated.