I'm a bit startled because whenever I write a comment, I only have a preview button.
Right, because you never enabled "No Force Preview". If you enabled "No Force Preview", then it would show both preview and create on the first form (edit: because it's not forcing you to preview). If you don't enable "No Force Preview" (the default), then your first form only shows the preview button (edit: because it is forcing you to preview).
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