Oh good grief... I had to look. Talk about a stretch. Anything that looks like an envelope is referencing an apron. The "F" in Facebook looks kind of similar to the walking cane in the Tubal-Cane mark.
These are ridiculous stretches.
But, you will see Freemason marks in many places. It is because these are historic and archetypal marks that stonemasons and early engineers used and many are used today in architecture and drafting, or the working tools represented real craftsman working tools (square, compass, right angle, level, etc).
It is because from their history, Freemasons took these drafting symbols and working tools and used them to create allegories for the lessons they were teaching. There is nothing mysterious about this. The history goes back to the early days of the craft, when many brothers were not literate or spoke different languages. The allegories created by symbols were an easy way to express a message and pass down a story.
