To support relative URLs from the backend, accessing the application via `http(s)://__DOMAIN__/proxy` will permanent redirect (302) to `http(s)://__DOMAIN__/proxy/` (trailing slash). Otherwise, a relative link like `<link rel="stylesheet" href="style.css">` would try to load `http(s)://__DOMAIN__/style.css` which would fail.
To support relative URLs from the backend, accessing the application via `http(s)://__DOMAIN__/proxy` will permanent redirect (302) to `http(s)://__DOMAIN__/proxy/` (trailing slash). Otherwise, a relative link like `<link rel="stylesheet" href="style.css">` would try to load `http(s)://__DOMAIN__/style.css` which would fail.