I recently commented on a question and I used the proper MathJax formatting for the numbers and letters:
Some minutes later my net became a little laggy and I refreshed the page. Then I lost my connection for a few seconds. The font of numbers changed a little for me as you can see in this screenshot:
Of course I refreshed the page again after my connection came back and the font got fixed.
What is the name of that incorrect font? Is it being used in math.SE or any other websites or applications?
Also, why did the format change when the connection was unstable?