Prevent WordPress from sending Cache-control http header
Thanks to @chrisguitarguy’s answer, you can control the http headers sent by WordPress via the “send_headers” hook. Here is the function I added to my theme’s functions.php file, and that solved the issue with the Varnish server. function varnish_safe_http_headers() { header( ‘X-UA-Compatible: IE=edge,chrome=1’ ); session_cache_limiter(”); header(“Cache-Control: public, s-maxage=120”); if( !session_id() ) { session_start(); } } … Read more