This is a kind 65535 event. Kind 65535 is the highest possible event kind in #Nostr.
Discussion
Testing linking to events of other kinds, part 2
nostr:nevent1qqsqhazmccv69q2wmn8tzmsmwtl43md0vq35x7n8yqspafcr9stcrpsfew5x6
SnapNostr can also do events aside from kind 1. Note ID of this is nostr:nevent1qqsqhazmccv69q2wmn8tzmsmwtl43md0vq35x7n8yqspafcr9stcrpsfew5x6
nostr:nevent1qqsqhazmccv69q2wmn8tzmsmwtl43md0vq35x7n8yqspafcr9stcrpsfew5x6