test image in signature below

I can't manage to add an image to my signature. Anyone help?

The code looks straight forward but did I make a typo?

[ img=http://www.minibb.com/forums/img/s.gif ][ /img ]
(no spaces)

Try tu insert some comment before the closing [/img], comments are mandatory.

I just noticed something else. Apparently https isn't recognized in the signature, where http is. So in the signature it is only possible to add a http-hyperlink to an image but not a https-hyperlink.

You may be right. but you need to send this bug-report (or feature request?) on the official miniBB forum. Here's not the right place for such subjects. Then you have more chances that Paul will fix it quickly.