vue-cli3 使用extend遇到错误，具体报错内容： [Vue warn]: You are using the runtime-only build of Vue where the template compiler is not available. Either pre-compile the templates into render functions, or use the compiler-included build....

webpack升级到了4.0版本了，但是在使用html-webpack-plugin插件时，报错，提示：TypeError: compilation.mainTemplate.applyPluginsWaterfall is not a function...