}
        return this;
      },
      /**
         Sets the current new-message audio alert URI (must be a
         repository-relative path which responds with an audio
         file). Pass a falsy value to disable audio alerts. Returns
         this. This setting is persistent. Returns this.
         this.
      */
      setNewMessageSound: function f(uri){
        delete this.playNewMessageSound.audio;
        this.playNewMessageSound.uri = uri;
        this.settings.set('audible-alert', !!uri);
        return this;
      }

    }
    if(cs.settings.getBool('monospace-messages',false)){
      document.body.classList.add('monospace-messages');
    }
    cs.inputMultilineMode(cs.settings.getBool('edit-multiline',false));
    cs.chatOnlyMode(cs.settings.getBool('chat-only-mode'));
    cs.pageTitleOrig = cs.e.pageTitle.innerText;

    const qs = (e)=>document.querySelector(e);
    const argsToArray = function(args){
      return Array.prototype.slice.call(args,0);
    };
    /**
       Reports an error via console.error() and as a toast message.
       Accepts any argument types valid for fossil.toast.error().

       using fossil.dom.append(), so may be of any type supported by
       that function.
    */
    cs.reportErrorAsMessage = function(/*msg args*/){
      const args = argsToArray(arguments);
      console.error("chat error:",args);
      const d = new Date().toISOString(),
            msg = {
            mw = new this.MessageWidget({
              isError: true,
              xfrom: null,
              msgid: -1,
              mtime: d,
              lmtime: d,
              xmsg: args
            }, mw = new this.MessageWidget(msg);
            });
      this.injectMessageElem(mw.e.body);
      mw.scrollIntoView();
    };

    cs.getMessageElemById = function(id){
      return qs('[data-msgid="'+id+'"]');
    };