media assets: fix show page to play Flash files.

app/javascript/src/javascripts/posts.js

@@ -36,13 +36,14 @@ Post.initialize_all = function() {
     this.initialize_post_image_resize_links();
     this.initialize_recommended();
     this.initialize_ugoira_player();
-    this.initialize_ruffle_player();
   }
 
   if ($("#c-posts #a-show, #c-uploads #a-show").length) {
     this.initialize_edit_dialog();
   }
 
+  this.initialize_ruffle_player();
+
   $(window).on('danbooru:initialize_saved_seraches', () => {
     Post.initialize_saved_searches();
   });