When a Sub Level is currently open (meaning it is listed as the persistent level in the levels window) and you save the level using the levels window the map build data registry will get destroyed.

This will cause an error when you open the persistent level using that sublevel.


  • While the sublevel is open using save all or right clicking the level in content browser and saving doesn't cause the bug to occur.
  • This can be resolved by rebuilding lighting and using save all in the main level using the sublevel.
Steps to Reproduce
  1. Open attached project
  2. Open Box_level
  3. In the levels window click the save level icon next to persistent level

Map Build Data Registry gets destroyed.

Map Build Data Registry remains intact.

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Affects Versions4.
Target Fix4.20
Fix Commit3920191
Main Commit4052378
Release Commit4095966
CreatedApr 20, 2017
ResolvedMar 2, 2018
UpdatedMay 31, 2018