Inline editing does not work for some fields in Jira
The option to edit a field "in-line" (without editing the whole issue) in Jira is not working for all the fields or is available only for some fields.
It is not possible to inline edit those fields which are not added to the Edit Issue screen for the screen scheme associated with the Project/Issue Type. You'll need to go to your Project Administration and edit your screen scheme to ensure this is in place.
Add the required fields to the screen associated with the Edit Issue operation in the respective screen scheme. Check out Project screens, schemes and fields for details on how to accomplish this.