Same effect.
If the plugin is disabled, I can preview a post when writing it e.g. when I’m logged in.
If the plugin is enabled and “Allow Anonymous Preview” is unchecked then I cannot preview the post even when logged in.
If plugin is enabled and “Allow Anonymous Preview” is checked, then I can preview the post both when logged in or logged out.
However I do want the preview to work when I’m logged in *before* making the article previewable by all.
