fixed media text handling

lib/single-file/css-fonts-minifier.js

@@ -133,7 +133,7 @@ this.fontsMinifier = this.fontsMinifier || (() => {
 		Array.from(rules).forEach(rule => {
 			if (rule.type == CSSRule.MEDIA_RULE) {
 				stylesheetContent += "@media " + Array.prototype.join.call(rule.media, ",") + "{";
-				stylesheetContent += processFontFaceRules(rule.cssRules, fontsDetails, rule.media, stats);
+				stylesheetContent += processFontFaceRules(rule.cssRules, fontsDetails, rule.media.mediaText, stats);
 				stylesheetContent += "}";
 			} else if (rule.type == CSSRule.FONT_FACE_RULE && (media.includes("all") || media.includes("screen"))) {
 				const fontInfo = fontsDetails.get(getFontKey(rule.style));