Switch your editor from visual to text mode and check if there are only shortcode on the page and nothing else.
If shortcode is wrapped with some html tags – try to remove them.
There is nothing but the shortcode. First thing I checked.
Here is the relevant page source, the extra <p> appears at the beginning of the entry content, before the plugin name comment:
<div class="entry-content">
<p>
<!-- Page-list plugin v.4.2 ww.wp.xz.cn/plugins/page-list/ -->
<ul class="page-list siblings-page-list ">
I have other shortcodes on other pages and there are no added <p> tags.
Correction – it’s only happening for the [siblings] shortcode, not [pagelist]
Oops upon further checking it seems to be generated by something else on this particular page – removed the pagelist shortcode and the <p> is still there. Sorry to waste your time.
It’s ok.
Check out the theme page template (page.php or single.php) file.
Templates are clean. It’s something related to NextGen galleries. Only happens on pages where one is placed. I’ll let them know. Thank you.