macOS version: El Capitan Version 10.11.6 (15G31)
Preview version: 8.1 (Version 877.7)
When I write a text box annotation, I can tell that text is going into the box when I write it, but the text box is not being resized. It is only a few pixels tall and there are no vertical resize indicators, only horizontal ones (hence I can tell that text makes it into the annotation because I can see the top of the letters in the first line of the text, but nothing else). No matter what font size I select, the same issue occurs.