如何配置YII2伪静态，有无后缀都可以访问，默认.html后缀

有无后缀都可访问，怎么默认url是.html后缀，直接上代码

'urlManager' => [
                    'enablePrettyUrl' => true,
                    'showScriptName' => false,
//                             'enableStrictParsing' => false,
//                     'suffix' => ".html",
                    'rules' => [
                            //'<controller:\w+>/<action:\w+>/<lang:\w+>'=>'<controller>/<action>',
                            '/<lang:\w+>/contact'=>'web/contact',
                            '/<lang:\w+>/index'=>'web/index',
                            '/contact'=>'web/contact',
                            '/contact.html'=>'web/contact',
                            '/index'=>'web/index',
                            '/index.html'=>'web/index',
                            '/<lang:\w+>'=>'web/index',
                    ],
            ],