1. Select Multiplayer -> "Host new session" -> LAN
2. Select any mission with a debug console
3. Open debug console and execute:
hint str [owner player, clientOwner]
It will report [2,2] which is correct.
4. Press ESC -> "Save and quit"
5. In the mission select screen, RESUME (not "restart"!) the same mission
6. Open debug console again:
hint str [owner player, clientOwner]
It will report [2,3] this time, which is wrong.