Why doesn't iceweasel see all css files?

Question

Browsers

The site includes the following styles:

<link href="/assets/884af1dd/themes/smoothness/jquery-ui.css" rel="stylesheet">
<link href="/assets/6102aa4f/css/bootstrap.css" rel="stylesheet">
<link href="/assets/3ee95211/css/style.css" rel="stylesheet">
<link href="/assets/469903/css/advert.css" rel="stylesheet">

All work, each file can be accessed directly from any browser.
The moment is that on debian 7.8 in the iceweasel browser all the styles that are in the advert.css file do not work. They simply don't exist.
If you go to the style sheet editor (css) in the iceweasel browser, there is simply no advert.css file.
In all other browsers everything is fine. Even in ie it's fine.
Please tell me what is the problem?