[TASK] Improve the format.nl2br docs (#209) (#210)

Releases: main, 13.4
(cherry picked from commit b35e508)

Co-authored-by: Lina Wolf <48202465+linawolf@users.noreply.github.com>

Author: typo3-docs-backport-bot[bot]

Documentation/Global/Format/Nl2br.rst

@@ -1,6 +1,3 @@
-..  Source: https://github.com/TYPO3/Fluid/blob/main/src/ViewHelpers/Format/Nl2brViewHelper.php
-
-:edit-on-github-link: https://github.com/TYPO3/Fluid/edit/main/src/ViewHelpers/Format/Nl2brViewHelper.php
 :navigation-title: format.nl2br
 
 ..  include:: /Includes.rst.txt
@@ -13,3 +10,53 @@ Format.nl2br ViewHelper `<f:format.nl2br>`
 
 ..  typo3:viewhelper:: format.nl2br
     :source: ../../Global.json
+    :display: tags,description,gitHubLink
+    :noindex:
+
+..  contents:: Table of contents
+
+..  _typo3-fluid-format-nl2br-example:
+
+Preserving line breaks in HTML output
+=====================================
+
+HTML ignores line breaks within text. To display text while preserving line
+breaks, you must convert newline characters such as `\\n` or `\\r\\n` into
+HTML line break elements :html:`<br />`.
+
+The `<f:format.nl2br>` ViewHelper uses PHP's
+`nl2br() <https://www.php.net/manual/en/function.nl2br.php>`_ function
+to insert HTML line breaks.
+
+..  code-block:: plaintext
+    :caption: User input
+
+    This is
+    a
+    string
+
+..  code-block:: html
+
+    <f:format.nl2br>{userInput}</f:format.nl2br>
+
+or inline:
+
+..  code-block:: html
+
+    {userInput -> f:format.nl2br()}
+
+..  code-block:: html
+    :caption: Output
+
+    This is<br />
+    a<br />
+    string
+
+..  _typo3-fluid-format-nl2br-arguments:
+
+Arguments of the `<f:format.nl2br>` ViewHelper
+==============================================
+
+..  typo3:viewhelper:: format.nl2br
+    :source: ../../Global.json
+    :display: arguments-only