While Using Explain Plan option in SQL Developer, getting below error (mentioned in screenshot).
There is no uncommitted transaction in the session.
I am getting this error even when first time opening SQL Developer.
It's a bug (27371100) - try upgrading your version of SQL Developer to at least version 18.1.
It's related to working with the plan table.
Latest versions shouldn't be committing/rolling back transactions based on an Explain Plan request.