Given my reason for clicking the link, I believe it's the first time I've seen her mentioned on HN. I likely would have clicked on any article with the name Frances in the title and remembered the name if I had ever seen it before.
Because I'm a woman, I actively keep my eye out for female role models. I have a fairly strong math background (for the world at large -- not for the HN crowd) and spent some time looking up info on Maryam Mirzakhani, the first female Fields Medalist, and even blogged about it at the time.
Given my interest in female role models and my personal association with the name Frances, I think I would have known the name had I ever seen it before. It would have likely stuck with me.
I've been here eleven years. It seems I've never seen her name before. And, in fact, if you search for it, it comes up (in the titles section, as part of a description, not really a title) only once ten years ago (until the past 24 hours).