Front.id

Here is a quick alternative to see which variables are available in a twig template when you don't have a debugger like xdebug.

It is especially useful when you want to verify that certain values are available to be printed in a particular template.

Simply put this snippet in the twig file you want to scan and it will print a list of the available variables (they will be printed in the position where you put the snippet):

<ol>
  {% for key, value in _context  %}
    <li>{{ key }}</li>
  {% endfor %}
</ol>

Result: 

Bye!