Adding notes and comments
As your graphs get bigger, it can get harder to keep track of what everything does. To help with this, you can add notes and comments.
Simply right-click a node in the editor and select "Add Comment". This will create a yellow colored text field where you can add your comments for that particular node. If you want to remove it, simply clear it, or right-click the node again and select "Remove Comment".
Adding notes (requires Unity 2020.1 and newer)
To add a standalone note. Right-click on the canvas in the editor and select "Add Note". The note consists of a title field and a content field. You can change the theme of a note and change the font sizes. Right-clicking on the note shows you the options to do this.
Notes on reference nodes are read-only and can't be changed. You'll need to change those on the original node.