Ticket #48709: 48709.3.diff

src/wp-admin/css/colors/_mixins.scss

@@ -39 +39 @@
         &:disabled,
         &.button-primary-disabled,
         &.disabled {
-                color: hsl( hue( $button-color ), 10%, 80% ) !important;
-                background: darken( $button-color, 8% ) !important;
-                border-color: darken( $button-color, 8% ) !important;
+                color: #606A73 !important;
+                background: #fbfbfc !important;
+                border-color: #a2aab2 !important;
                 text-shadow: none !important;
         }
 }