show error message of the image cannot be obtained

Hey,
not wanting to start another issue as my experience is somewhat similar.

Freshly installed Cookbook app on Nextcloud server does not want to use images from a URL.

If I create a new recipe, add Title, description ingredients etc and point the image to a URL (i.e.: https://upload.wikimedia.org/wikipedia/commons/thumb/5/5d/Skwarki.jpg/960px-Skwarki.jpg) this is not retrieved.
I updated the image with a local file and the thumbnail was generated. If I point at a remote image this doesn't change and still shows local file. No amount of cache refresh helps.

When trying to import a recipe from a website the URL and other info is pulled correctly and the image is also shown.

NC 33.0.5
Cookbook 0.11.7

Originally posted by @dzidek23 in #2076

Reproduce the problem by creating a recipe with the supplied remote image URL, then compare it with a locally uploaded image and with an imported recipe. Start by tracing the image retrieval entry point used for new recipes; done means a failed remote-image retrieval is reported with a visible error message instead of silently retaining the local image.