Finally investigated and traced the fat zaps to some kind 1512 events. What are these events and what client is generating them?

https://njump.me/nevent1qqsp4kprwdzythjerv8rc7qdagd03v65npq4wz6q3vrjzjuf7mpjy7qpzemhxue69uhhyetvv9ujumn0wd68ytnzv9hxgq3qpr4du5xl28dy5sh4msz9uddnwxgzupkk4qzjzklv84edc6ruevzqgw32ts nostr:note1r9qnqkpxsp9twttawtqzp3e2xx3yql6e7ce9x0sy0zz6nz4f952q3nj2e4