Update docs/configuring-playbook-etherpad.md (#3954)

* Update docs/configuring-playbook-etherpad.md: add the common section "Extending the configuration"

Signed-off-by: Suguru Hirahara <acioustick@noreply.codeberg.org>

* Update docs/configuring-playbook-etherpad.md: add the option to configure the default pad text

Signed-off-by: Suguru Hirahara <acioustick@noreply.codeberg.org>

* Update docs/configuring-playbook-etherpad.md: remove the detail about setting the unmaintained Dimension default to the Etherpad instance

We have recommended users to avoid installing Dimension since it was deprecated, so it is no longer sensible to discuss how it could be integrated with Etherpad.

This commit also removes the known issue section as it describes the issue which can be experienced on Dimension only.

Signed-off-by: Suguru Hirahara <acioustick@noreply.codeberg.org>

* Update docs/configuring-playbook-etherpad.md: minor changes

- Update the internal anchor link (follow-up to 04b32af0c1)
- minor edits

Signed-off-by: Suguru Hirahara <acioustick@noreply.codeberg.org>

* Apply the feedback

Signed-off-by: Suguru Hirahara <acioustick@noreply.codeberg.org>

---------

Signed-off-by: Suguru Hirahara <acioustick@noreply.codeberg.org>
Co-authored-by: Suguru Hirahara <acioustick@noreply.codeberg.org>

docs/configuring-playbook-etherpad.md

@@ -43,6 +43,30 @@ After changing the domain, **you may need to adjust your DNS** records to point
 
 If you've decided to reuse the `matrix.` domain, you won't need to do any extra DNS configuration.
 
+### Configure the default text (optional)
+
+You can also edit the default text on a new pad with the variable `etherpad_default_pad_text`.
+
+To do so, add the following configuration to your `vars.yml` file (adapt to your needs):
+
+```yaml
+# Note: the whole text (all of its belonging lines) under the variable needs to be indented with 2 spaces.
+etherpad_default_pad_text: |
+  Welcome to Etherpad!
+
+  This pad text is synchronized as you type, so that everyone viewing this page sees the same text. This allows you to collaborate seamlessly on documents!
+
+  Get involved with Etherpad at https://etherpad.org
+```
+
+### Extending the configuration
+
+There are some additional things you may wish to configure about the component.
+
+Take a look at:
+
+- [etherpad role](https://github.com/mother-of-all-self-hosting/ansible-role-etherpad)'s [`defaults/main.yml`](https://github.com/mother-of-all-self-hosting/ansible-role-etherpad/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 `etherpad_configuration_extension_json` 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:
@@ -66,34 +90,18 @@ ansible-playbook -i inventory/hosts setup.yml --tags=setup-all,ensure-matrix-use
 
 The Etherpad UI should be available at `https://etherpad.example.com`, while the admin UI (if enabled) should then be available at `https://etherpad.example.com/admin`.
 
-If you've [decided on another hostname or path-prefix](#adjusting-the-etherpad-url) (e.g. `https://matrix.example.com/etherpad`), adjust these URLs accordingly before usage.
+If you've [decided on another hostname or path-prefix](#adjusting-the-etherpad-url-optional) (e.g. `https://matrix.example.com/etherpad`), adjust these URLs accordingly before using it.
 
 ### Managing / Deleting old pads
 
-If you want to manage and remove old unused pads from Etherpad, you will first need to able Admin access as described above.
+If you want to manage and remove old unused pads from Etherpad, you will first need to create the Etherpad admin user as described above.
 
-Then from the plugin manager page (`https://etherpad.example.com/admin/plugins`, install the `adminpads2` plugin. Once installed, you should have a "Manage pads" section in the Admin web-UI.
+After logging in to the admin web UI, go to the plugin manager page, and install the `adminpads2` plugin.
 
-### How to use Etherpad widgets without an integration manager (like Dimension)
+Once the plugin is installed, you should have a "Manage pads" section in the UI.
 
-This is how it works in Element Web, it might work quite similar with other clients:
+### Integrating a Etherpad widget in a room
+
+**Note**: this is how it works in Element Web. It might work quite similar with other clients:
 
 To integrate a standalone Etherpad in a room, create your pad by visiting `https://etherpad.example.com`. When the pad opens, copy the URL and send a command like this to the room: `/addwidget URL`. You will then find your integrated Etherpad within the right sidebar in the `Widgets` section.
-
-### Set Dimension default to the self-hosted Etherpad (optional)
-
-If you decided to install [Dimension integration manager](configuring-playbook-dimension.md) alongside Etherpad, the Dimension administrator users can configure the default URL template.
-
-The Dimension configuration menu can be accessed with the sprocket icon as you begin to add a widget to a room in Element Web. There you will find the Etherpad Widget Configuration action beneath the _Widgets_ tab.
-
-#### Removing the integrated Etherpad chat
-
-If you wish to disable the Etherpad chat button, you can do it by appending `?showChat=false` to the end of the pad URL, or the template.
-
-Example: `https://etherpad.example.com/p/$roomId_$padName?showChat=false`
-
-## Known issues
-
-If your Etherpad widget fails to load, this might be due to Dimension generating a Pad name so long, the Etherpad app rejects it.
-
-`$roomId_$padName` can end up being longer than 50 characters. You can avoid having this problem by altering the template so it only contains the three word random identifier `$padName`.