For the Server Connector (P2 connector), when I create a JIRA issue with the Create endpoint button, a new tab/windows will prompt that allow me edit JIRA issues after the issue get created.
Cloud connector should also have this feature that will open a new tab/windows upon creation.
The P2 Connector assumes that everyone in Salesforce has access to JIRA. The new connector removes the need for this (i.e. a Salesforce user does not need to have access to JIRA, and vice versa). If a Salesforce user needs to manually edit a JIRA information, I would encourage to focus on that problem - why is there such need? Is there something we should support in the mapping or the 'Review & Create" screen in Salesforce?