anchor.diff:  
     /* If post_idx is on the immediate border of what's already displayed, add it incrementally, and
      * we'll cull extra posts later.  Otherwise, clear all of the posts and populate from scratch. */
  -  if(post_idx == this.posts_populated[1])
  +  if(post_idx === this.posts_populated[1])
     {
       this.add_post_to_display(true);
       return;
     }
  -  else if(post_idx == this.posts_populated[0])
  +  else if(post_idx === this.posts_populated[0])
     {
       this.add_post_to_display(false);
       return;
  
positive.code:      */
      var post_id_search_order = sort_array_by_distance(old_post_ids.slice(0, old_centered_post_idx+3), old_centered_post_idx);
      var initial_post_id = null;
      for(var i = 0; i < post_id_search_order.length; ++i)
      {
        var post_id_to_search = post_id_search_order[i];
        var post = Post.posts.get(post_id_to_search);
        if(post != null)
        {
          initial_post_id = post.id;
          break;
  
negative.code:   }
  
    var target = e.target;
    if(target.tagName === "INPUT" || target.tagName === "TEXTAREA")
      return false;
  
    if(key === 63) // ?, f
    {
      debug("xxx");
      document.fire("viewer:show-help");
  