Show template data

To display the data in a template, you can use the dump() function.
If you only need the data of certain variables, you can pass this as an argument:

{{ dump() }} {# output all available data #}
{{ dump(a) }} {# output the data of variable "a" #}
{{ dump(a, b) }} {# output the data of variable "a" and "b" #}
Example

Output of the heading of the text element

{# /templates/content_element/text.html.twig #}
{% extends "@Contao/content_element/text.html.twig" %}
{% block text %}
    {{ dump(headline) }}
{% endblock %}

If you want the output to be in the toolbar - and not in the template - you can use the dump function:

{% dump %} {# output all available data #}
{% dump(a) %} {# output the data of variable "a" #}
{% dump(a, b) %} {# output the data of variable "a"  und "b" #}

Note that in extended templates the dump() function must be used inside a block.

Since the evaluated data may contain safety-critical information about the system, this is only possible if Debug mode is enabled.