vaScript/Reference/Global_Objects/String">String</a> / HTMLElement</span></span></span><span class="qm-api-header-tags"></span></div></div></div></div><div class="qm-api-collapsible-content"><div class="qm-api-item-content"><div class="qm-api-description"><div class="qm-html-paragraph">A css selector or element to use when constructing the  <span class="qm-api-type-standalone qm-code-font"><span class="qm-api-type">ButtonGroup</span></span> </div></div></div></div></div><div class="qm-api-item qm-api-javasc