code: function _processOnKeyUp__noWords(evt) {
          let key = evt.keyCode || evt.which;
          let char = String.fromCharCode(key);
          if (key == 13) {
              this._onSelectedCB(this._input.value);
          }else if (/[a-zA-Z0-9-_ ]/.test(char) || key === 8){
              let prefix = this._input.value;
              if (prefix != '')
                  this._keyListenerDebounced(prefix);
          }
      }
docs: Listen to a keyup event on the search input. This function will NOT handle navigation
  inside the words ui widget.
  
  @param {event} evt - Keyup event