Hello Stefan,

I tried your example in my development environment and received no errors.  On further examination I found this difference -- with your example, the react and react-dom packages are being used in the Webpack bundle, whereas my application uses react and react-dom externally.

I have the following in my webpack.config.js file:

module.exports = {
    ...
    externals: {
        "react": "React",
        "react-dom": "ReactDOM"
    }
    ...
}

and in my page I include these two modules externally, before including the bundle script:

    <script type="text/javascript" src="<%= ResolveClientUrl("~/node_modules/react/umd/react.development.js") %>"></script>
    <script type="text/javascript" src="<%= ResolveClientUrl("~/node_modules/react-dom/umd/react-dom.development.js") %>"></script>
    <script type="text/javascript" src="<%= ResolveClientUrl("~/Scripts/dist/main.js") %>"></script>

When I do this, the invalid props warning occurs.  Is there a way to use React externally like this and not get the warning?

Thank you,
Nathaniel