@Frank Furman there's no way to lock them. Using the API you could automatically remove lists added by people who aren't admins for example.
Might be better just to ask people not to create new lists, though.
Another question might be: why do they feel the need to create new lists? Perhaps there's an opportunity to improve the workflow or board design
If you had to thrive a new habit during a lockdown, what would it be? Trello
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