[lacks info] v3.6.0 Map cannot be changed when lacking slots

[tomreyn]

I'm not sure what exactly led to this situation, but very recently some of us were connected to a headless server and player uuu was controlling it. uuu reported that he was unable to change maps in this situation. It is unclear to me how to reproduce this, help is appreciated.

It is also noteworthy that on the screenshot below, uuu, the player controlling the server, was not displayed in the list of connected players at all.

Screenshot:

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