Update what's new

dist/preview release/what's new.md

@@ -106,6 +106,7 @@
 - Use min/max values from position accessors (when available) to set the bounding box of meshes ([Popov72](https://github.com/Popov72))
 - Added missing "pluginExtension" parameter to SceneLoader.ImportAnimations. ([phenry20](https://github.com/phenry20))
 - Added support for .glb file loading through a base64 encoded filename ([Popov72](https://github.com/Popov72))
+- Fixed issue with loading screen hiding too early when loading multiple assets concurrently. ([bghgary](https://github.com/bghgary))
 
 ### Serializers