Templating: is it right?

This is my template file item.html.twig

{% extends 'partials/base.html.twig' %}
{% block content %}
  <div class="flex-container content">
    <div class="flex-box subpage-title">
      {{ header.title }}
    </div>
    <div class="flex-box subpage-content">
      <img src="{{ page.url }}/image.jpg">
      <div class="subpage-text">
        {{ content }}
      </div>
    </div>
    <div class="flex-box back-link">
      <a href="{{ base_url }}">Zurück</a>
    </div>
  </div>
{% endblock %}

And this is in my base.html.twig

<div class="background-3">
  {% block content %}
  {% endblock %}
</div>

My browser renders a blank page .... :(

It looks fine. Is your page called item.md ?

If you view source, what HTML do you get in your browser?

on my local machine everything looks just fine. but on my server there is simply a blank screen !

I have to say that "item.md" is called as a child of many children elements ... maybe that helps !?!?!?

Does your server have the correct version of PHP?

maybe ??!?!? how can i check this ?

add a php check file on your server and call it up.

http://www.liquidweb.com/kb/how-to-check-php-modules-with-phpinfo/

7.0 or 5.6 or 5.5 or 5.4 ? I have the opportunity to choose what i like ....

I have not tried 7.0, but 5.6 is a good bet

currently i am using 5.6 !

does your server have the required modules listed here: http://learn.getgrav.org/basics/requirements

so i have to mention that the homepage is shown.... except the subpage is not showing !

You say blank page, could be a PHP error. Perhaps you can look in your php error log or turn on displaying of php errors: http://stackoverflow.com/questions/1053424/how-do-i-get-php-errors-to-display

where should i place the lines

ini_set('display_errors', 1);
ini_set('display_startup_errors', 1);
error_reporting(E_ALL);

?

My parent MD file of the page that does not show up looks like ...

title: Posts
content:
  items: @self.children
---

maybe here a problem ?

That ini_set stuff needs to be in your .htaccess file.

hey people. now i have an 404 error, after disabling ADBLOCK !!!!! at least something.

Check the 404 troubleshooting docs now.