Thanks @danbp for that toggle snippet, nearly five and a half years later and still works a treat!
Two questions if I may:
1 Is it possible to default to hidden?
2 Is it possible to move the button to another position?
I’m testing Youzify which may complicate things as it appears where I want to move it to is behind a Youzify component that only appears once a comment has been posted.
From what I understand (which in coding is very little sadly) your code searches for the “Comment” button and inserts the toggle button after it: