Test to reproduce (for TestApp2.7z

Steps:

1. Run the test application "TestApp2" (on the window will be displayed name of slide for "Parent_Component" and applied opacity 0 for "Child_Component" via Slide)
2. Press key "0" (simultaneously changes slide of "Parent_Component" for apply opacity 100 for "Child_Componnet" and  set visibility to true for "Child_Componnet")
3. Close application.
4. Run step "1" again

Result:

After 9 starts

NOTE!! 4 times out of 9 has been loaded "Child_Componnet" with visibility: true and opacity: 100, but component invisible or opacity: 0.
And 5 times out of 9 has been loaded "Child_Componnet" with visibility: true and opacity: 100, but on window has been loaded Master slide (not default slide "Slide_A") for "Child_Componnet".

For more understand please refer to test application TestApp2.7z and video MasterSlideIssue.7z (in attach)

This issue is regression between qt3dStudo v2.7 and v2.8.