The vertical blue line is when the DOM is fully parsed and the scaffolding is up, the DOM is
The red line represents when the document's assets have all been downloaded and the screen has been painted with them, hence
Here you can see both those lines in action on Alice in Videoland:
The load screen hides the experience until all the background images have been loaded, being removed inside
Give the 600ms delay between
load, it's a good thing we had that load screen, or that first scene would have no background! for almost a second, causing a spectacular "wink!"