Restructuring Removes Background Image Trick

[jmwebservices]

For UAs not supporting SVG as background images, there is a nice fallback which CSSO restructuring destroys.

.selector {
    background-image: url( 'image.png' );
    background-image: url( 'image.svg' ), none;
}

Results in:

.selector {
    background-image: url(image.svg),none
}

This is similar to https://github.com/css/csso/issues/415 albeit for a different property.