@Fabian I think I found the issue. It seems that Nostur expects full nip96 like response in blossom nip94 tags, while BUD08 just states tags array of arrays under nip94 field, nothing else. Initially I got it wrong too, and returned it as your check does. Now it is fixed and complies with BUD08 specs.

GitHub

nostr-essentials/Sources/NostrEssentials/NIP-96/UploadResponse.swift at d6f550579d15c850635c7c1ae73a7f4f6b80d1f6 · nostur-com/nostr-essentials

Start building your project with these nostr essentials - nostur-com/nostr-essentials

GitHub

nostr-essentials/Sources/NostrEssentials/Blossom/BlossomUploadResponse.swift at d6f550579d15c850635c7c1ae73a7f4f6b80d1f6 · nostur-com/nostr-essentials

Start building your project with these nostr essentials - nostur-com/nostr-essentials

GitHub

nostr-essentials/Sources/NostrEssentials/Blossom/BlossomUploader.swift at d6f550579d15c850635c7c1ae73a7f4f6b80d1f6 · nostur-com/nostr-essentials

Start building your project with these nostr essentials - nostur-com/nostr-essentials