Contao template inheritance allows overwriting only certain sections of a template (blocks).
Many templates already structure their contents by wrapping it with $this->block('name-of-the-block') and
$this->endblock() statements. Only contents wrapped in such blocks can be adjusted.
First, the base template must be declared with $this->extend('name-of-the-template'). Then you can provide new block
content by wrapping it in $this->block('name-of-the-block') and $this->endblock() statements like in the original
template.
The original block content is available via $this->parent().
The fe_page.html template contains multiple blocks (such as head, meta, body, footer). If we only want to add
another meta tag, we could write the following:
<?php $this->extend('fe_page'); ?>
<?php $this->block('meta'); ?>
<?php $this->parent(); ?>
<meta name="author" content="John Doe">
<?php $this->endblock(); ?>