Larian Studios Forums Divinity: Original Sin 2 Divinity - Original Sin 2 - Bugs & Technical Problems DEBUG_PROFILE_1's turn.

My wife, playing Lohse as a mage specialized in Aero and Hydro, somehow joined as DEBUG_PROFILE_1 when joining the game of our host, another friend.
While that is nothing more than a visual annoyance, apparently she could not access her inventory, which probably means she was loaded as some form of mock-profile or player whose inventory is disable during deployed play.
Sadly she closed her game before I could screenshot it, but the combat in question where we noticed the issue was at about (X: 688, Y: 157).

The current profile is listed in the main menu, under the profile button.
Generally, the Debug_Client_Profile_1 profile is created if you start the game again when it is already running (to test something in co-op on a single computer, or create multiple custom party members). That shouldn't block accessing the inventory, though.