Logging in, and seeing a different account's character selection screen

[CatsEyeXI]

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• [x] I have specified what branch this happens on branch: base

Additional Information (Steps to reproduce/Expected behavior) :

im encountering an issue where under some undetermined condition, a user can log in and to another account's character selection screen. ive seen this before personally (dualboxing on the same machine), and someone posted a screenshot of it happening to them on my discord.

potentially this has happened to a player and his character was deleted. i have a backup from a few days ago, could you possibly provide any guidance on how exactly i can restore the his character data from a backup sql file? or at least which tables i would need to grab rows from...