You can do it by removing the "Assign" permission from the user. See https://confluence.atlassian.com/display/JIRA/Managing+Project+Permissionsfor more details on how to change the project permissions.
removing Assign permission will also removing the ability to assign in the workflow, which may not be what we want here.
I think this has to be done as referred by this KB
Hi awesome community! In this article, I would like to describe the one of the toolset (service) for the analyze some problems on different Java-based instances, of course, as Atlassian admini...
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