Get the value of a field to do an if statement Twig

I am trying to generate a PDF with Entity Print. Until then all is well.

In my Twig page, I try to make conditional displays. But I can’t get the conditions to work.

I render my fields using {{ content.field_custom }} and that also works fine.

But the condition don't work , when I do something like :

{% if content.field_custom == 'John' %} ...

or

{% set field = content.field_custom %}
{% if field == 'John' %}
   <p>Hello</p>
{% endif %}

I need to do this in the fields twig template, can someone help me?

Many thanks

I recommend the Twig Field Value module, which provides a field_value filter that you can apply directly to a field:

{{ content.field_name|field_value }}

Also, while this doesn't specifically answer your question, I would be remiss not to mention the handy and useful Twig Tweak module. It rocks! :)