It is possible to assign a custom icon for a content type: https://doc.ezplatform.com/en/latest/guide/extending_ez_platform/#custom-content-type-icons

Then this icon appers in the "Create content" popup and in the create content page too, but when viewing a content of the affected type (in the admin ofc), a different icon is rendered (more often an empty icon).

The built in locationview.html.twig file uses the content type identifier as icon name, so it tries to render something like this: 

/bundles/ezplatformadminui/img/ez-icons.svg#content_type_identifier

I would expect that, if a thumbnail is set, then that icon appers here too.

Reproducing:

• create a custom content type
• set a thumbnail for it, like:

  thumbnail: /bundles/ezplatformadminui/img/ez-icons.svg#folder

• create a content of this type
• after the redirect, you can see the icon is missing