SGS/www/app/Http/Middleware/EnsureIsTinfoilClient.php

<?php

namespace App\Http\Middleware;

use Closure;
use Illuminate\Http\RedirectResponse;
use Illuminate\Http\Request;
use Illuminate\Http\Response;

class EnsureIsTinfoilClient
{
    /**
     * Handle an incoming request.
     *
     * @param  Closure(Request): (Response|RedirectResponse)  $next
     */
    public function handle(Request $request, Closure $next): Response|RedirectResponse
    {
        if ((bool) $request->header('theme')) {
            return redirect()->route('tinfoil');
        }

        return $next($request);
    }
}