Oh and btw, the outfit was probably extremely rare, I've only found one source that tells us a doctor was wearing it in France, but it didn't quite look like the one we all know and many of the contemporary depictions were likely just made up:

brill.com/view/journal...

There are a few dated 1656, one of Italian origin (British Museum, published by Sebastiano Zecchini). Intriguing certainly!

There are no known eyewitness accounts or regulations from the early modern period mentioning plague doctors wearing beaky masks. All these popular images trace back to one picture that is specifically related to Rome, including Manget's, and that one is probably a satire.