I am trying to port this over to v6, however, it appears that I have not gotten the syntax correctly. this code works perfectly when using react-router v5.
I know for instance that the routing syntax changes.
Urls.js
import React from "react";
import { BrowserRouter, Route, Switch, Redirect } from "react-router-dom";
import Login from "./components/Login";
import Home from "./components/Home";
// A wrapper for <Route> that redirects to the login screen if you're not yet authenticated.
function PrivateRoute({ isAuthenticated, children, ...rest}) {
    return (
      <Route
        {...rest}
        render={({ location }) =>
        isAuthenticated ? (
            children
          ) : (
            <Redirect
              to={{
                pathname: "/login/",
                state: { from: location }
              }}
            />
          )
        }
      />
    );
  }
In react-router-dom version 6 gone are custom Route components, replaced by wrapper components that handle the logic of rendering content or the redirect.
An example replacement could be as follows:
const PrivateWrapper = ({ isAuthenticated, children }) => {
  const location = useLocation();
  
  return isAuthenticated ? (
    children
  ) : (
    <Navigate to="/login" state={{ from: location }} />
  );
};
Usage:
<Routes>
  <Route
    path="...."
    element={(
      <PrivateWrapper isAuthenticated={....}>
        <SomeProtectedComponent />
      </PrivateWrapper>
    )}
  />
</Routes>
And to make the PrivateWrapper a little more usable it can render an Outlet instead of a children prop for nested Route components to be rendered into.
const PrivateWrapper = ({ isAuthenticated }) => {
  const location = useLocation();
  
  return isAuthenticated ? (
    <Outlet />
  ) : (
    <Navigate to="/login" state={{ from: location }} />
  );
};
Usage:
<Routes>
  <Route element={<PrivateWrapper isAuthenticated={...} />} >
    <Route path="...." element={<SomeProtectedComponent />} />
    ..... other protected routes  ......
  </Route>
</Routes>