Texture rendering issues in SceneLoader

The first time dynamically changing source of SceneLoader to new scene (3d model), there is something wrong with rendering textures (of all or part of entities), they are black or gray (in another project sometimes colorful rubbish).

Changing source after that to something else, and then back to first model - everything is rendered as should. See video attached.

Example based on qgltf attached - there is two 3d models exchange each other as source for SceneLoader by timer.

It seemed that bug is only appear when there more than one object in a loaded scene. It can be seen in that texture of teeth of wolf model is rendered right for the first time.

I'm using almost the latest qt 5.7 commit: 50559ea3325c0215da155911836c0416d0027716