I have subscribed to this site's newsletter. I received the email but it has broken anchor tag at the end. The screenshot is of mobile screen but it is there in web also.
I ran into this a while back and it turned out that Gmail truncates messages that are "too long", and this truncation breaks the final link and/or gravatar. (Presumably it's breaking in the middle of the href and so can't render the anchor text and/or image.) This is made worse by SE using ginormous links to support their analytics; 100k just doesn't go as far as it used to.
If you're using Gmail, look for the tiny "message clipped" message at the bottom (easy to miss!) and click that to see the full message. If that's not your problem -- you're seeing the full message, no apparent clipping, yet the display is messed up -- please let us know.