Editing a Template from the Create / Edit Issue dialog v1.2.0
To edit a Template, open Create Issue or Edit Issue dialog and apply a Template which needs to be updated, update all the field values and hit Update Template at the bottom of the dialog:
Update Template button is available for public Template, only if you're an Administrator or a Template owner.
You can also switch Project and (or) Issue Type to access different set of fields on the Screen.
However, once the Template is updated, only the fields available on the current Screen will be saved, clearing the values for any missing field on the current Screen in the Template.
Once clicked, the Edit Template dialog will appear, allowing you to change the Template details:
Click Update button to persist changes to your Template.