Avoid that people use the domain name instead of a hostname. (#5768)

I found the text confusing.

Author: monty241

tutorials/configure-nextcloud-ubuntu/index.mdx

@@ -58,9 +58,9 @@ It provides a large portfolio of [different applications](https://nextcloud.com/
 
 By default, access to your Nextcloud Instance is limited to `localhost`. To access it via your domain name, you have to add it to the list of trusted domains.
 
-Run the following command to allow the connection via the domain `your.domain.com` to your Nextcloud.
+Run the following command to allow the connection via the hostname `nextcloud_name.your_domain.com` to your Nextcloud. Replace `nextcloud_name` by the intended hostname and `your_domain.com` by your top level domain, e.g. `nextcloud.acme.eu`.
     ```
-    nextcloud.occ config:system:set trusted_domains 1 --value=your.domain.com
+    nextcloud.occ config:system:set trusted_domains 1 --value=nextcloud_name.your_domain.com
     ```
 
 The following message should appear, confirming that the domain was added: `System config value trusted_domains => 1 set to string your-domain.com`
@@ -105,11 +105,11 @@ By default, the Nextcloud installation via Snap provides a plain HTTP connection
     ```
 3. Enter your email address when prompted and confirm by pressing **Enter**:
     ```
-    Please enter an email address (for urgent notices or key recovery): you@your.domain.com
+    Please enter an email address (for urgent notices or key recovery): you@nextcloud_name.your_domain.com
     ```
-4. Enter the domain name that you have configured in a previous step for your Instance (`your.domain.com` in our case), then confirm by pressing **Enter**:
+4. Enter the domain name that you have configured in a previous step for your Instance (`nextcloud_name.your_domain.com` in our case), then confirm by pressing **Enter**:
     ```
-    Please enter your domain name(s) (space-separated): your.domain.com
+    Please enter your domain name(s) (space-separated): nextcloud_name.your_domain.com
     ```
 The following output should display once the certificate has been obtained:
     ```
@@ -121,8 +121,8 @@ The following output should display once the certificate has been obtained:
 
 You can now access your Nextcloud Instance.
 
-1. Open your browser and type the address of your Instance (For example: `https://your.domain.com`). A login screen displays.
+1. Open your browser and type the address of your Instance (For example: `https://nextcloud_name.your_domain.com`). A login screen displays.
 2. Enter the username and password that you have created in the previous steps. Your personal cloud storage space displays.
 3. Upload, share, or download files from the interface:
     <Lightbox image={image} alt="" />
-4. Optionally, download one of the several [Nextcloud clients](https://nextcloud.com/install/#install-clients) to manage your cloud storage space directly from your computer.
+4. Optionally, download one of the several [Nextcloud clients](https://nextcloud.com/install/#install-clients) to manage your cloud storage space directly from your computer.