In the list of search result screen there is the new cover button for the full preview of the cover in a browser. The intention was to enable this button, if the corresponding placeholder %_coverfullurl% for the url of the full cover is present and contains an url, and otherwise disable it.
Actually I found out that this check seems to use the placeholder %_coverurl% for cover thumbnails instead. This is observable if e.g. only one of both urls is present.
Some sources need to construct the cover URL based on a standardized pattern without knowing if the target file actually exist. If the thumbnail URL returns HTTP 200, it's very likely that the provided full cover URL also exists (and obviously, I can't download all full covers for a list that might have plenty of results).
Sorry but this seems to be a misunderstanding because I was not clear enough.
I wanted to say that this issue exists, if no url at all is contained in the placeholders. It's about the placeholder for full cover preview being empty, then the button should be disabled and not if the placeholder for the thumbnail is empty (not present), as this is what currently happens.
If my script can't find an url for a thumbnail, but one for full preview, the full preview butten is disabled, although the url 'is present'.
I don't want the target of any url being checked if it exists.
I think I understood, but as I said, I'm using the successful download of the thumbnail as condition to enable the preview button of the full cover. This is by intention.
So you're suggesting to also enable the preview button if no thumbnail URL, and only a full cover URL is provided. Which script is affected by that?
My new project deals with ARD-Mediathek. Not all videos have a 1x1 image, that could be used as cover thumbnail. And non square images do not please me as thumbnails, because of their aspect ratio is not being preserved ( see here Preserve aspect ratio for non square cover thumbnails ). If you could fix that, I would also use rectangular thumbnails, and consequently always have thumbnail and full cover urls.
Thumbnail is missing:
Rectangular Thumbnail is distorted:
I think I'll do both, enable the cover button if no thumbnail URL but a full cover URL is provided, and correct the aspect ratio. I'll keep you posted.
Moved to General Discussion to be treated as an improvement of an existing feature.