Merge pull request #4041 from luixxiul/fix

Update docs to add the section "Extending the configuration"

docs/configuring-playbook-prometheus-grafana.md

@@ -53,6 +53,14 @@ After changing the domain, **you may need to adjust your DNS** records to point
 
 **Note**: It is possible to install Prometheus without installing Grafana. This case it is not required to create the CNAME record.
 
+### Extending the configuration
+
+There are some additional things you may wish to configure about Prometheus.
+
+Take a look at:
+
+- [Prometheus role](https://github.com/mother-of-all-self-hosting/ansible-role-prometheus)'s [`defaults/main.yml`](https://github.com/mother-of-all-self-hosting/ansible-role-prometheus/blob/main/defaults/main.yml) for some variables that you can customize via your `vars.yml` file. You can override settings (even those that don't have dedicated playbook variables) using the `prometheus_configuration_extension_yaml` variable
+
 ## Installing
 
 After configuring the playbook and potentially [adjusting your DNS records](#adjusting-dns-records), run the playbook with [playbook tags](playbook-tags.md) as below:

docs/configuring-playbook-sliding-sync-proxy.md

@@ -36,6 +36,14 @@ If you've changed the default hostname, you may need to create a CNAME record fo
 
 When setting, replace `example.com` with your own.
 
+### Extending the configuration
+
+There are some additional things you may wish to configure about the component.
+
+Take a look at:
+
+- `roles/custom/matrix-sliding-sync/defaults/main.yml` for some variables that you can customize via your `vars.yml` file
+
 ## Installing
 
 After configuring the playbook and potentially [adjusting your DNS records](#adjusting-dns-records), run the playbook with [playbook tags](playbook-tags.md) as below: