I did a sanity check and looked in Xcode, in the templates for a new target, I don't see 'Quick Look Preview Extension' in the visionOS' list (I do see 'thumbnails').
Could it not be possible yet? That would explain why no issues when making the app 'designed for iPad'.
I suppose the issue disappears if you remove vision as a target for the quick look extension.. but maybe you want the extension in visionOS as well.
I read some more and I came to the conclusion that the Quick Look preview extensions are not yet for visionOS, but only someone from Apple can confirm that.
Topic:
Developer Tools & Services
SubTopic:
Xcode
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