message: changed icon for the select button
diff: <input id="command-target" list="command-target-list" type="text"><i id="target-" class="fa fa-chevron-down" aria-hidden="true"></i>
  <div id="target-dropdown" class="w3-dropdown-content w3-bar-block">
  </div>
  - <button id="selectElementButton" class="btn_sf"><i class="si si-select" aria-hidden="true"></i></button>
  + <button id="selectElementButton" class="btn_sf"><i class="si si-inspect" aria-hidden="true"></i></button>
  <button id="showElementButton" class="btn_sf"><i class="si si-find" aria-hidden="true"></i></button>
  </div>
  <datalist id="command-target-list">
  