It's because "nostr:" prefix is included 8n the link
Discussion
Yeah nostr:npub18m76awca3y37hkvuneavuw6pjj4525fw90necxmadrvjg0sdy6qsngq955 “helps” you by randomly inserting things like that.
Try this, rabble: https://nostr.com/nevent1qqsqfsxmh3r7hpfp4dkj86gct6h0ugm2jahwn26agu9p3qvlcuanssgqe9mfe