Recently, a message appeared explaining that annotations are soon to be gone forever. If you don't know what an annotation is, it's a little, clickable button that allowed you to link viewers to other videos, or to leave an important note. Unfortunately, they didn't work on mobile, so rather than fixing them so that they do, YouTube has decided to get rid of them completely and replace them with end cards, a convenient feature that saves time but can't do half of the things annotations could. Great...