The Yellow Notes box, useful for many games, has special value in Hangman It can serve at least 2 purposes.

The first is that you can enter the theme of the game that you're playing so you don't need to scroll down below the game for each different game.

You type in the theme/category and hit the Update Notes button. The next time you play, and thereafter, that note will appear at the top of the game page.

The second is that it offers the perfect way to keep track of your progress during a puzzle. When you guess a word within a theme, put it in the notes box [I capitalize it] and when it's your turn again, you don't have to try to remember it.
You can also put in suggestions for your next guess while it's fresh in your mind.

I've learned to make heavy use of that Notes Box and find it very helpful.