if( m.fmime
              && m.fmime.startsWith("image/")
              && Chat.settings.getBool('images-inline',true)
            ){
            contentTarget.appendChild(D.img("chat-download/" + m.msgid));
            ds.hasImage = 1;
          }else{
            // Add a download link.
            const downloadUri = window.fossil.rootPath+
                  'chat-download/' + m.msgid+'/'+encodeURIComponent(m.fname);
            const w = D.addClass(D.div(), 'attachment-link');
            const a = D.a(downloadUri,
              // ^^^ add m.fname to URL to cause downloaded file to have that name.
              "(" + m.fname + " " + m.fsize + " bytes)"
            )
            D.attr(a,'target','_blank');
            D.append(w, a);
            if(/\.html$/i.test(m.fname)){
              /* Add an option to embed HTML attachments in an iframe. The primary
                 use case is attached diffs. */
              D.addClass(contentTarget, 'wide');
              const embedTarget = this.e.content;
              const btnEmbed = D.button("Embed", function(){
                D.remove(btnEmbed);
                const iframe = document.createElement('iframe');
                D.append(embedTarget, iframe);
                iframe.addEventListener('load', function(){
                  iframe.style.maxHeight = iframe.style.height
                    = iframe.contentWindow.document.documentElement.scrollHeight + 'px';
                });
                iframe.setAttribute('src', downloadUri);
              });
              D.append(w, btnEmbed);
            }
            contentTarget.appendChild(w);
          }
        }
        if(m.xmsg){
          if(m.fsize>0){
            /* We have file/image content, so need another element for
               the message text. */
            contentTarget = D.div();