HTTP HEAD requests not supported
Trying to use HTTP HEAD to see if a Tweet exists returns 404, instead of a 200 OK. Using GET works okay.

For example (choosing a completely random tweet I had a link for):

Jul06:1519 @ack:~ $ curl -I https://nitter.net/Neuronmisfire/status/628011819878236162
HTTP/1.1 404 Not Found
Server: nginx/1.14.1
Date: Mon, 06 Jul 2020 19:19:23 GMT
Content-Type: text/html;charset=utf-8
Content-Length: 3122
Connection: keep-alive
Strict-Transport-Security: max-age=31536000; includeSubDomains; preload

Jul06:1520 @ack:~ $ curl -o /dev/null -s -D - https://nitter.net/Neuronmisfire/status/628011819878236162 
HTTP/1.1 200 OK
Server: nginx/1.14.1
Date: Mon, 06 Jul 2020 19:21:30 GMT
Content-Type: text/html;charset=utf-8
Content-Length: 4911
Connection: keep-alive
Strict-Transport-Security: max-age=31536000; includeSubDomains; preload
Content-Security-Policy: default-src 'none'; script-src 'self' 'unsafe-inline'; img-src 'self'; style-src 'self' 'unsafe-inline'; font-src 'self'; object-src 'none'; media-src 'self' blob:; worker-src 'self' blob:; base-uri 'self'; form-action 'self'; frame-ancestors 'self'; connect-src 'self' https://*.twimg.com; manifest-src 'self'
X-Content-Type-Options: nosniff
X-Frame-Options: DENY
X-XSS-Protection: 1; mode=block
Referrer-Policy: no-referrer


If I remember correctly, this behavior is forbidden in the HTTP RFC's.
