Place the following in the server block of your sites nginx config, ie /etc/nginx/sites-enabled/example.com
# Allow CORS
add_header 'Access-Control-Allow-Origin' '*' always;
add_header 'Access-Control-Allow-Credentials' 'true' always;
add_header 'Access-Control-Allow-Methods' 'GET, POST, PUT, DELETE, OPTIONS' always;
add_header 'Access-Control-Allow-Headers' 'Accept,Authorization,Cache-Control,Content-Type,DNT,If-Modified-Since,Keep-Alive,Origin,User-Agent,X-Requested-With,hx-current-url,hx-request,hx-target,hx-t>