nginx shows warning when using custom templates: [warn] the "listen ... http2" directive is deprecated, use the "http2" directive instead

Symptoms

• The following error when testing the NGINX configurations for syntax errors:

  # nginx -t
  nginx: [warn] the "listen ... http2" directive is deprecated, use the "http2" directive instead in /etc/nginx/plesk.conf.d/vhosts/example.com.conf:7

• Custom templates are in use

Cause

The custom templates refer to the deprecated directives.

Resolution

1. Connect to the server via SSH
2. Remove or correct the custom templates under /usr/local/psa/admin/conf/templates/custom/domain/

3. Disable the http2_pref:

   # plesk bin http2_pref --disable

4. Re-enable it:

   # plesk bin http2_pref --enable