I am editing a multi-Medium entry.  I have gone back and forth between the multiple Medium within the Release, each time using the "Track Parser" to bring up the current values of the Medium Tracklist, and pasting in updated values from my editor.  At some point during this process, there became a disconnect between the "Tracklist" and the "Track Parser".  The below screenshot shows the result of clicking "Track Parser" on "Medium 1".  I believe the "Track Parser" is correct; each time I click on "Track Parser" I get this same result.  But the Tracklist shows stale values.

It is not easy to keep the edit session open for you to investigate.  So I will save the session and see how it goes.