I realize this issue has a previous bug report, but it was resolved and closed 2 years ago.  It came back in the recent update.

When I put maps in the Ender Chest and reload the world, they are named "Unknown Map" until I take them out and view them.  The name then returns to normal and the map content is as it should be.  It's just really annoying to have to open each map to find the right one.