stylesheets/bourbon/css3/_user-select.scss in bourbon-compass-2.1.3 vs stylesheets/bourbon/css3/_user-select.scss in bourbon-compass-3.0.1

@@ -1,3 +1,3 @@
 @mixin user-select($arg: none) {
-  @include prefixer(user-select, $arg, webkit, moz, ms);
+  @include prefixer(user-select, $arg, webkit moz ms spec);
 }