Why pdf thumbnails cause page bad looking?

Question

When I use Mediawiki's CommentStreams extension with code below:

== Guide ==
[[File:TerraformingMars.pdf|page=1|thumb|right|راهنمای فارسی - سایت: بازی نوین، مترجم: نیما مسقدی]]

== Comments ==
<comment-streams/>

Why does it look bad as here: But if I move Guide section below Comments it works fine? How to fix it? It seems pdf thumbnailing has problem with anything after it, and it must be the last one?

Answer 1

The image has float positioning so the content that follows it will be laid out alongside it. If you don't like that, don't float it (use e.g. center instead of thumb) or put something like Wikipedia's {{clear}} template after it.