It's not an f. 200-300 years ago a lower-case s just simply looked a lot like an f. It was the style back then in both handwriting and typeface too. An f didn't have the curved hook at the bottom and an s did. The s was supposed to look like an elongated landau bar with a short horizontal bar thru the middle. It was considered stylish and sophisticated in a time when few people were literate and formally educated. It fell out of style and over the years the lower case s evolved into the familiar shape we now know.
I called for this at #276...ever since I truly positively hoped this wouldn't happen!