The concept Adding something to the content during saving and considering all sorts of possible MarkUp isn’t an easy task. I played around a bit with it and decided that the best chance would be to use PHP native \DOMDocument class to parse the content, identify the paragraph and add the HTML comment to it. … Read more
The function you’re using, wp_link_pagesCodex, does not have the feature you’re looking for by default. However you can easily extend it by using a callback function, registered as a filter on that functions arguments: add_filter(‘wp_link_pages_args’, ‘wp_link_pages_args_prevnext_add’); The filter will then modify the parameters that are used in that function on-the-fly and inject the missing links … Read more