Ah yes, that’s exactly it, thanks!
@james_katz that’s not an invalid tx per se, the txid won’t appear in zcashd-backed block explorers due to the issue hanh mentioned, but it is showing up in my zebra mempool for example.
I’ll surface this to the Zebra team.
(For anyone reading, while it would be better to filter those, they’re not super harmful since they need to pay the ZIP-317 fee anyway. The dust filtering rule is not a consensus rule)
Also I’d guess this is related to the zerdinals thing