The other day, when I was looking through my exported Facebook posts, I saw something flash up over the toolbar icon for uBlock Origin, my ad-blocker of choice. Curious, I clicked to open up the info panel, and was informed that the local web page on my Mac was connecting to fbcdn.net. Annoyed, I added that domain to my block list.
Given that the archive I downloaded from Facebook before deleting my profile last year contains all the pictures I posted there, as well as the text of message, I'm entirely unclear as to why those web pages are connecting to Facebook's CDN servers.
This morning, after some sleuthing using the Web Inspector, I tracked down the link. It's buried inside the minified inline CSS in the header of the page, and also over the section where my profile picture would appear in the top-of-page Facebook navigation bar.
I have a hard time believing that this isn't intentional, no doubt another data-point to add to their 'shadow profile' on me.