Sorry to reply late.
If your webpack.config.js doesn't have 'mode' property, you have to add 'mode' property into your webpack.config.js.
The below is an example.
module.exports={mode:'production',// <= It is necessary to resolve the warningentry:{'index':[path.resolve(__dirname,'src/index.js')]},output:{filename:'[name].js',path:path.resolve(__dirname,'public'),publicPath:'/',},plugins:[newwebpack.DefinePlugin({'process.env.NODE_ENV':JSON.stringify(process.env.NODE_ENV)})],module:{rules:[{test:/\.(js|jsx)$/,use:'babel-loader',},]},resolve:{extensions:['.js','.jsx'],},};
Sorry to reply late.
If your webpack.config.js doesn't have 'mode' property, you have to add 'mode' property into your webpack.config.js.
The below is an example.
Thank you for reading this post.
Hello, Masashi Hirano.
It's seems im miss something in the past, here is examples ) github.com/webpack/webpack/tree/ma...
Anyway, thx ) for response.