Didn't see an Image in Firefox 37.0.2 / OSX & Win)

[Nasuada]

For some strange reasons I can't see the image who I placed as header image in a private phpBB board.
It works great under Safari or Opera, but FF didn't show anything. The image is completely removed without any spacer.

[Nasuada]

Well done, I solved it by self. I found the problem in the inspector of Firefox. There I found the error around loading the jquery.min.js from google over this URL: https://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js. Firefox say, it's something around Mixed-Content when I'm on a https page who deliver simple http URLs (see the Info here: https://developer.mozilla.org/en-US/docs/Security/MixedContent).
So I changed the URL to the jquery file to a https URL and now it works.