Ghost tabs in experimental version 701

In version 5.0.7 (701), when closing a file tabs (having are several files opened on the editor), and empty tab remais visible, and some glitches seem to take place in the UI.

I am aware that version 701 is marked as "experimental", so I am just reporting this in case it is useful for debugging and refining the new builds.

Thank you for info. Screenshot would be helpful