HTML Compressor and SVG Filters

[addedlovely]

When using SVG filters in CSS - which reference an inline SVG file - the HTML compressor appends the theme directory to the path (breaking the filter).
filter: url('#blur');

Gets transformed to:
filter: url('/wp-content/themes/bespoke/style.css#blur')

Expected behavouir would be to not append the URL to the path.

Seen in Comet Cache Pro (v170220).