It happens frequently to have a page beginning by one or more break lines.
It's linked to templates, which should be corrected.
But just avoiding to render them would improve the page layout.
Looking for "<p><br /></p>" just after <!-- start content --> should do the trick.
By example for this page:
http://fr.wikipedia.org/w/index.php?title=DisplayPort&oldid=60280474
Version: unspecified
Severity: enhancement