diff --git a/scss/_mixins.scss b/scss/_mixins.scss
index defb76a60b..f33e496505 100644
--- a/scss/_mixins.scss
+++ b/scss/_mixins.scss
@@ -172,9 +172,6 @@
 // --------------------------------------------------
 
 @mixin placeholder($color: $input-color-placeholder) {
-  &:-moz-placeholder { /* Firefox 18- */
-    color: $color;
-  }
   &::-moz-placeholder { /* Firefox 19+ */
     color: $color;
   }