[BLOCKING] Ingame map items don't update

Windows_Minecraft - Release_853103
(RC 1.4)

Summary:
Maps will not update. Any previously created map will remain static, and any new maps will be blank.

Impact:
This makes maps useless except as decoration.

Repro Steps:
1. Open world
2. Make a map

Observed Results:
The map will remain blank. Any maps previously existing on this world will still display an image, but the image will not update properly.

Expected Results:
Maps should show an updating overhead view of the area around the player, as they are meant to.

Screenshots/Videos attached:
Note the mismatch between blocks and map:
https://i.imgur.com/qOVG2rb.jpg

This map was just created:
https://i.imgur.com/O6NkzLn.jpg