How to do a wildcard proxy with 3.0?

[SantoJambit]

With 2.x I had the following code:

app.use(
            "*",
            createProxyMiddleware({
                target: "http://localhost:4200",
                changeOrigin: true,
            })
        );

This would forward all unknown requests (not already handled by express) to a separate server. In 3.0, this always responds with the index page of http://localhost:4200, rather than the specific sub-page that was actually requested.

I don't see how I can do this with 3.0. Nothing in the migration guide seems to point to anything like it.

Thanks in advance