TinyMCE RTL in course bulk email

common/lib/xmodule/xmodule/js/src/html/edit.coffee

@@ -66,6 +66,8 @@ class @HTMLEditingDescriptor
         schema: "html5",
         # Necessary to preserve relative URLs to our images.
         convert_urls : false,
+        # Sniff UI direction from `.wrapper-view` in studio or `.window-wrap` in LMS
+        directionality: $(".wrapper-view, .window-wrap").prop('dir'),
         content_css : tiny_mce_css_links.join(", "),
         formats : {
           # tinyMCE does block level for code by default