The link to bug reporting site from this page http://www.videolan.org/support/#bugs, actually links to httpS://www.videolan.org/support/#bugs.
As such, there is no certificate when https://www.videolan.org/support/#bugs loads & Firefox issues a warning. The actual site is accessible w/o secure connection, so I'm not sure if there used to be a secure trac site, or someone just made a typo setting up the link on above page.
Possibly, links from other pages to trac site also show incorrect https.