Every blue eye from a single individual mutation? Really?

[Northern_Piper]

Previous threads on topic (including one started by OP of this thread three years ago) :

Why blue eyes?

Looking at the map of the distribution of blue eyes in Europe made me wonder: why do Europeans have blue eyes? Were they found in other parts of the world before European expansion and inter-marrying? https://unsafeharbour.files.wordpress.com/2012/02/maps-europelighteyes.jpg?w=584

How are blue eyes adaptive?

I’ve wondered about this before, but was reminded of it after seeing Nora O’Donnell on the nightly news. For her, and many others, crystal blue eyes are a strikingly attractive feature. But do they serve another purpose? That eye color seems so out of keeping with the rest of color schemes on the outside of the human body. Inform me.

All blue-eyed people share one common ancestor

This can’t possibly be true. This would mean that the blue-eye mutation happened only ONCE in all of the history of homo sapiens. What am I missing here?