No problem. Full credit to Salar Ali from @copilot 
For the HTML header, it’s just a cosmetic addition. You don’t need it (but you might want it). The purpose is to hide the scrollbar of the repeating group that can appear with some browsers (or when you’re in incognito mode on Chrome apparently).
Without scrollbar:
With scrollbar (removing the HTML header and visiting the site on Chrome with incognito mode on):
I found that small piece of magic 
code somewhere on the forum but I can’t remember which thread. Some variations of it allow you to control the style of the scrollbar if you prefer.