Pagespeed neue Regel - Avoid CSS @import

[piratos]

Eine interessante Sache ist die neue (ab 1.9.1) Regel Avoid CSS @import - das ist etwas was enorm vebreitet ist, aber fatale Auswirkungen hat:

Using CSS @import in an external stylesheet can add additional delays during the loading of a web page.
Details

CSS @import allows stylesheets to import other stylesheets. When CSS @import is used from an external stylesheet, the browser is unable to download the stylesheets in parallel, which adds additional round-trip times to the overall page load. For instance, if first.css contains the following content:

@import url("second.css")

The browser must download, parse, and execute first.css before it is able to discover that it needs to download second.css.
Recommendations

Use the <link> tag instead of CSS @import
    Instead of @import, use a <link> tag for each stylesheet. This allows the browser to download stylesheets in parallel, which results in faster page load times:

    <link rel="stylesheet" href="first.css">
    <link rel="stylesheet" href="second.css">