location = /tubesync {  
        return 301 https://$host/tubesync/;
}

location ^~ /tubesync/ {
        rewrite ^/tubesync/(.*) /$1 break;
        proxy_pass http://127.0.0.1:4848/tubesync/;
        proxy_set_header Host $host;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Host $host;
        proxy_set_header X-Forwarded-Proto $scheme;
        proxy_redirect off;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection $http_connection;
}