It's really, really easy to see "data leak", see an email address, and assume that this is really bad.
On the other hand, if you actually look at what these pages are, they're Checkout pages, not Transaction pages. Coinbase sellers generated these pages and intentionally linked to them. Someone even mentions this in the fourth comment on the linked page.
On the other hand, if you actually look at what these pages are, they're Checkout pages, not Transaction pages. Coinbase sellers generated these pages and intentionally linked to them. Someone even mentions this in the fourth comment on the linked page.