World is initialized twice when opened through the Content Browser

When opening a Level from the Content Browser, the world gets initialized twice. This initialization process can be quite long, especially for big world using world partition.

There doesn't seem to be any apparent reason this would be needed.

Looking into it, it seems the issue might come from ContentBrowserAssetDataCore.cpp within EditOrPreviewAssetFileItems(..) function which first load the asset and then ask the asset editor subsystem to open the asset's editor. Both those actions have a path into initializating the world:

Reproduction Steps:

• Open Unreal Insight
• Open Unreal Editor (-trace=default -statnamedevents)
• Through the Content Browser open a Level by double clicking on it

Result:

• Unreal Insight shows the UWorld being initialized twice in a row

Expected Result:

• Opening a Level should only initialize the UWorld once