[html] Complete list of reasons why a css file might not be working

New one for you Guys !

During my Gulp minification process

<!-- build:css /css/project-mini.css -->
    <link rel="stylesheet" href="css/main.css"/>
    <link rel="stylesheet" href="css/splash.css"/>
    <link rel="stylesheet" href="css/header.css"/>
    <link rel="stylesheet" href="css/print.css" media="print"/>
<!-- endbuild -->

Last CSS file was for print and the generated output gave me

    <link rel="stylesheet" href="css/project-mini.css" media="print"/>

So because of media="print" all CSS rules were skipped !