Less than a second here. Yes, I can see it paint, but it's nowhere near 5 seconds. And I'm on a base model Thinkpad T440, hardly a speed machine these days.
Which site did you test it on? All of the developer tools (Chrome, Firefox, Safari, Edge) will take awhile to load a massive DOM tree with many thousands of nodes.
EDIT: Okay, tested again; it depends heavily on the website you do this on.