React Router works locally but 404s on Vercel when I refresh

[themintytoast]

I deployed my React app to Vercel using react-router, and routing works when I click around the app.
But if I refresh the page or directly open a URL like /about, it shows a 404 page.
There are no errors in the logs.

[sameersharmadev]

This is not an issue with react router, its because Vercel does not support client side rendering out of the box.
Simplest fix is to just serve index.html on each route by adding vercel.json in your root directory with:

{
    "rewrites": [{ "source": "/(.*)", "destination": "/" }]
}