Yup, remove the abilities for the users to Edit and/or Schedule. You have to have both those permissions to be allowed to rank issues.
Actually, anyone that have the 'Schedule Issue' and 'Edit Issue' permissions for the issue you want to rank will be able to do that. You might have to restrict those permissions to the groups you want in order to prevent other people from ranking issues.
@Jack Graves [AC] first caught our eye with his incredible breakdown of what, in his opinion, can make or break a Jira software implementation. (Read his thoughts on this thread)! In this follow...
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