I posted an answer on Stack Overflow and it's one of my first few answers. I entered almost the entire paragraph from this page that starts with "If n_1" and ended at "and its depth is 0." as well as an image and then another paragraph below.
When I tried to bold a few sentences within the quote and posted, many sentences were lost. My post is here: What is the difference between tree depth and height?
I'm using Mac OS X El Capitan and Google Chrome.
I'm aware the subscripts mean italics but kinda determined that it wasn't my issue. First I tried deleting the post pictured and making a new post without the subscripts, but the same thing was happening, so I never saved that edited post, and just undeleted the post pictured.