OK, it probably didn't go through, but I got further using a "vanilla" Chrome browser.
I tried to place an order. At the point of submitting the order, the market demanded my NSEC which I declined to share.
I let it default to generating a new one.
Then the whole thing hung up with a spinning "waiting" indicator, probably? because no wallet.
Seems the market system needs a fallback to present an LN invoice QR code?