&& (prevMessage
               ? !this.messageIsInView(prevMessage)
               : false)){
          /* If a new non-history message arrives while the user is
             scrolled elsewhere, do not scroll to the latest
             message, but gently alert the user that a new message
             has arrived. */
          if(!f.btnDown){
            f.btnDown = D.button("⇣⇣⇣");
            f.btnDown.addEventListener('click',()=>this.scrollMessagesTo(1),false);
          }
          F.toast.message("New message has arrived.");
          F.toast.message(f.btnDown," New message has arrived.");
        }else if(!this._isBatchLoading && e.dataset.xfrom===Chat.me){
          this.scheduleScrollOfMsg(e);
        }else if(!this._isBatchLoading){
          /* When a message from someone else arrives, we have to
             figure out whether or not to scroll it into view. Ideally
             we'd just stuff it in the UI and let the flexbox layout
             DTRT, but Safari has expressed, in no uncertain terms,

          D.removeClass(f.elemsToToggle, 'hidden');
          D.removeClass(document.body, 'chat-only-mode');
        }
        ForceResizeKludge();
        return this;
      },
      /** Tries to scroll the message area to...
          <0 = top of the message list, >1 = bottom of the message list,
          <0 = top of the message list, >0 = bottom of the message list,
          0 == the newest message (normally the same position as >1).
      */
      scrollMessagesTo: function(where){
        if(where<0){
          Chat.e.messagesWrapper.scrollTop = 0;
        }else if(where>0){
          Chat.e.messagesWrapper.scrollTop = Chat.e.messagesWrapper.scrollHeight;

    settingsPopup.options.adjustY = function(y){
      const rect = settingsButton.getBoundingClientRect();
      return rect.top - popupSize.height -2;
    };
  })()/*#chat-settings-button setup*/;

  (function(){ /* buttons to scroll to the begin/end of the messages. */
    E1('#chat-scroll-bottom').addEventListener('click',function(ev){
    Chat.e.btnMsgEnd.addEventListener('click',function(ev){
      ev.preventDefault();
      Chat.scrollMessagesTo(1);
      return false;
    });
    E1('#chat-scroll-top').addEventListener('click',function(ev){
    Chat.e.btnMsgHome.addEventListener('click',function(ev){
      ev.preventDefault();
      Chat.scrollMessagesTo(-1);
      return false;
    });
  })();
  
  /** Callback for poll() to inject new content into the page.  jx ==