Ticket #56578: 56578.patch

wp-content/themes/twentyfifteen/css/editor-blocks.css

@@ -344 +344 @@
 .edit-post-visual-editor a,
 .editor-block-list__block a,
 .wp-block-freeform.block-library-rich-text__tinymce a {
-        border-bottom: 1px solid #333;
-        color: #333;
+        border-bottom: 1px solid currentColor;
+        color: currentColor;
         text-decoration: none;
 }
 

wp-content/themes/twentyfifteen/style.css

@@ -648 +648 @@
  */
 
 a {
-        color: #333;
+        color: currentColor;
         text-decoration: none;
 }