ton id="presentationMode" class="toolbarButton presentationMode hiddenLargeView"
                title="Switch to Presentation Mode" tabindex="31" data-l10n-id="presentation_mode">
                <span data-l10n-id="presentation_mode_label">Presentation Mode</span>
              </button>

              <button id="openFile" class="toolbarButton openFile hiddenLargeView" title="Open File" tabindex="32"
                data-l10n-id="open_file">
                <span data-l10n-id="open_file_label">Open</span