Please "View All" or "Page View" or some option to help. Also, how to underline?

I have been trying to enjoy the "Show More" function these boards use, but it is really irritating on large threads. Can we have a way to specify how much more we want to show, or show all, or a page count, or anything to help us keep our place?

Side question: how do I underline? I see only bold, italic, and strike-through.

Thanks!