Only user users who have Edit permission Edit can input the values.
On the issue screen Issue Screen, Jira have has two mode modes ( issue create, issue viewIssue Create, Issue View).
In issue create Issue Create mode, Edit permission Edit is required. The user users can chosen choose the values in the custom field.
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In issue view Issue View mode, the user users who have View/ Edit permission view or edit will see the value of the custom field.
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Click on this custom field to go to Edit mode.
if user
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If the users don’t have such permission:image don’t have permission.
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if the custom field is not configure.
image don’t have configure.
Number Field Security get Group Picker gets the value from the chosen custom field on the Issue. The application will process the value (encode to store it, decode to show it).