Steps to reproduce

1. Install Ibexa DXP v4
2. Create a new content type with one image asset field
3. Add a new image under the media/images folder
4. Create content using created CT
5. Publish
6. Edit ibexa.yaml and add under the site the following code:

    content_view:
        full:
            editor_articles:
                template: '@ibexadesign/full/image_assets.html.twig'
                match:
                    Id\Content: 67 #use id from created content 

1. Create a template under /templates/themes/standard/full/image_assets.html.twig with the following code:

{% extends '@ibexadesign/pagelayout.html.twig' %}

{% block content %}
{% set image_variation = ibexa_image_alias(content.getField('field_643d1c1c07928'), content.versionInfo, 'medium') %}

{{ dump(image_variation) }}

{% endblock %} 

1. Go to created content in frontend

Result

The image_variation variable will be null

Expected

The object Ibexa\Contracts\Core\Variation\Values\ImageVariation should appear

Note

When analyzing this issue, I found the PR that is responsible for this issue: https://github.com/ibexa/core/pull/185, currently we have two tags with the same name:

         tags:
             - { name: 'ibexa.media.images.variation.handler', identifier: 'alias' }

So currently one is always overwritten, in this case, Ibexa\Bundle\Core\Imagine\Variation\ImagineAwareAliasGenerator is always used when setting IBEXA_VARIATION_HANDLER_IDENTIFIER=alias.