code: function () {
                  this._proxyFixSize();
  
                  if (!this._sInitialFocusId) {
                      var sInitFocusId = _fnGetInitialFocus(this);
  
                      // Compare the initial focus id with the current focus that is
                      // stored in the FocusHandler in the core.
                      // If the initial focus was set properly already by the Popup
                      // don't focus twice. Because Internet Explorer will be confused with// TODO remove after 1.62 version
                      // two focusin and focusout events
                      if (sInitFocusId !== sap.ui.getCore().getCurrentFocusedControlId()) {
                          var oControl = jQuery(document.getElementById(sInitFocusId));
                          oControl.focus();
                      }
                  }
  
                  if (!this._sResizeID) {
                      // register the ResizeHandler for the content of the toolPopup and not the whole toolPopup itself.
                      // In this way when resized the toolPopup does not change its height indefinitely.
                      this._sResizeID = ResizeHandler.register(this.$('content')[0], this._proxyOnResize);
                  }
  
                  // forward the Popup's opened event accordingly
                  // was added in "1.19.0" as a fix for a CSN and was downported to "1.18.2" and "1.16.6"
                  this.fireOpened();
              }
docs: Function is called via 'jQuery.proxy()' when the ToolPopup has been opened
  including the fade-in-animation of the Popup
  
  @private