WordPress insert automatically paragraph tags <p> and </p> for separate content breaks within a post or page. In the visual or HTML view of the post content in editor, paragraph tags never appear. Of course this is generally a useful feature. But sometimes it creates a lot of troubles for programmers and template designers.
If, for some reason, you want or need to remove this automatic behavior, you can add the following line of code into your functions.php file.
remove_filter('the_content', 'wpautop');
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