I think when someone drags-and-drops items on a Kanban board, it's considered the same as if they had just edited that record and changed the corresponding field that the Kanban lanes are based on. So you could potentially modify their role permissions within the app so they're read-only, which would prevent them from making any changes, or you could just lock down that particular field that the Kanban is based on.
If you still want them to be able to modify that field in other contexts (like if they click directly into the record) then I'm not sure how to lock it down in just the Kanban report. I think the point of a Kanban, normally, is specifically so that you can click-and-drag to move items around, as a quicker or more intuitive way of organizing certain information (like the status of certain records). I could be wrong though.
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Jake Rasmussen
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