force
Begins loading the resources of the given blocks and their children. If the resource had been loaded earlier and resulted in an error, it will be reloaded. Note: This function is useful for preloading resources before they are needed. Warning: For elements with a source set, all elements in the source set will be loaded.
Parameters
blocks
the blocks whose resources should be loaded. The given blocks don't require to have resources and can have children blocks (e.g. a scene block or a page block). Pass an empty list to load resources for every block currently known to the engine.