With Ubuntu 16 I can run both local and remote (via xrdp) desktop Xsessions simultaneously with the same account. With Ubuntu 18 I can log in remotely with xrdp or log in locally via the physical keyboard and mouse, but not both. A local login precludes a remote login, and vice versa. I've confirmed with a test just now that this is new behavior with Ubuntu 18.
The more I test and tinker with this the more I'm concluding that this is not really a specific issue with xrdp but rather a limit on the number of Xsessions a user can have running simultaneously. Does this sound familiar to anyone? Is there a config parameter in X or the desktop manager that limits the number of simultaneous logins from an account? I've confirmed that this behavior exists in both Ubuntu 18 and Xubuntu 18, so I don't think it is the desktop manager doing this - must be X? This does not affect SSH logins - I can have as many of those running as I like. Again it takes me back to X and the number of sessions allowed.
