is there a built-in solution for shopware 6 apps to be previewed? For example my app shows messages and I want the shop owner to see the messages in a preview before he activates the messages globally in the shop. How do I obtain this functionality? Thank you very much for help.
There's no such thing out of the box. If the preview doesn't have to be behind an authentication and may just broadly be hidden, then you could use a query parameter to decide on showing the message, even if the general display is turned off.
{% if config('MyApp.config.globallyActive') or app.request.query.has('previewEnabled') %}
<p>My Message visible if globally active or preview is enabled</p>
{% endif %}
Then inform the shop owner to visit a page where a message would be shown using the previewEnabled
query parameters:
http://shop.example.tld/some-page-with-the-message?previewEnabled