Theme development

Are there any themes that looks like this http://gaviasthemess.com for D8 but build totally with public modules?

Gavias uses closed non public modules with limited flexibility.

I am having difficulty getting a theme installed.

All other Drupal themes I have had no trouble installing, but this one is different. 

I am using Drupal 8.6.0 through GoDaddy's Installatron. Once installed, I go to "Appearance" (within administration) to upload a new theme, but it does not allow the URL file path or to BROWSE in the zipped file to directly upload it. FYI: I did the updates and there is still no URL/upload link. So, I tried extracting it through the File Manager...

Hi,

when I use any date filter in Drupal 8 Twig variable, I see error with blank screen.

{{ node.field_date|date('j.n.Y') }}
or
{{ node.field_date|date("j.n.Y") }}
or
{{ node.field_date.value|date('j.n.Y') }}
or
{{ node.field_date|raw|date("j.n.Y") }}

Exception: DateTime::__construct() expects parameter 1 to be string, array given v DateTime->__construct() 

Some other Twig variable filters are ok (|reverse  |lower etc.)

Thank you very much for your help.

Josef F.

I'm new to Twig templating and I'm curios how to work with objects within twig.

Currently I'm having struggle with this simple template (and I need much more complex ones) where start is a DateTime object.

<span>
{{ start.format('H:i:s')
</span>

I'm getting a Twig_Sandbox_SecurityError:

Calling "format" method on a "DateTime" object is not allowed.

Do I really have to manually register every single method I like to call within a Twig template?

Thanks

Matthias

I've created a module. In this module, I've created a custom form with some parameters. In theses parameters, I have this field : 

    $form[self::DESCRIPTION_PAGE] = array(
      self::TYPE => 'text_format',
      self::TITLE => $this->t("Description de la page"),
      self::DEFAULT_VALUE => $config->get(self::DESCRIPTION_PAGE),
      '#format'=> 'creation_de_contenue',
    );

Where #format'=> 'creation_de_contenue' is my custom CKEditor. 

I've created three taxonomy vocabularies on the site I'm currently working on, and added an image field to each of them, for an icon representing each term. And I have a content type that includes a term reference field for each of the three vocabularies. What I would like to do is have the content type display the icon for the chosen term, rather than the name of the term. I'm guessing there are a few different ways to do this...