Hi Cody,
Thanks for the reply. We are streaming in sublevels using LevelStreamingDynamic::LoadLevelInstance(). Probably because of that we are not hitting the delegate you mentioned. I’m also seeing this ensure in a Windows packaged build. In the process of the level streaming in we use a material to cover the screen with a full screen transition, and then we wipe our UI and replace it with the appropriate UI for the new level we are showing.
For a bit more tech detail, we are attaching a layout widget to the game viewport, which uses a derivation of CommonActivatablePanel as its base class. The widget has a canvas panel with slots for our UI elements. Each slot is an instance of CommonActivatableWidgetContainerBase, though we only have one widget at a time in them right now.
This main layout widget has the game instance as its parent and is marked to never be destroyed. It is created and attached from a GameInstanceSubsystem on BeginPlay.