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Issue level permissions

Issue level permission can be achieved through "dynamic user" fields which values can differ on an issue basis (e.g. "Assignee" or "Group Custom Field"). 

That is not clearly described in JIRA documentation hence most users are not aware of this consequence of using "dynamic user" fields in permission scheme. 

Screenshot below present WORK ON ISSUES permission configured on an issue level basis:

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Hide Time Tracking add-on 

Hide Time Tracking add-on checks project level permissions and, in most cases, is not aware of the single issue environment, i.e. permission depending on the Assignee or Group custom field. Therefore it is not recommend to use issue level permissions because Hide Time Tracking add-on might not hide time tracking information correctly. 

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