What "add selection as New Note" does?
When I right click a selected text there's an option to add it as a New Note, what that does?
It adds the selected text you selected and then adds that text as a note into the notes panel. If you click on it, and then go into your notes panel, you'll see your selected text is now listed as a note. This is great if you want to take some text on a website and take a note of it, and is easier and faster than just copy/pasting the note.