lxm---修复app-popover组件在火狐浏览器存在兼容性问题

src/utils/app-popover/app-popover.tsx

@@ -230,7 +230,7 @@ export class AppPopover {
         // 阻止事件冒泡
 
         event.stopPropagation();
-        const element: Element = event.toElement;
+        const element: Element = event.toElement || event.srcElement;
         if (element.hasAttribute('app-popover-tag')) {
             const tag: any = element.getAttribute('app-popover-tag');
             if (Object.is(this.activePopoverTag, tag)) {