Got me jittery too. There will be people sleeping soundly with their bitcoin in offline cold storage that won't know they've been hit for years. I might have over reacted. I have used Mk3 and maybe generated seeds with it. Couldn't recall. Passphrases and multisig prob would have kept me safe anyhow. Thought better safe than sorry so rolled into new wallets anyhow. Would have preferred to do it more leisurely. At least stopped me putting off a few improvements that I'd intended.
As a bit of wallet hygiene, I use message signing as a way to validate that signers (multisig or single sig) work. Does nothing to protect against a bodgy RNG but gives some peace of mind that backups and collaborators function. Handy for new setups or long established ones. Can download and run offline: https://gatekeeper.dpinkerton.com
