Fortunately, it didn’t fall off into the roasting pan:
The lens slides right out of that nicely curved and crimped housing, the rim ID of which should be slightly smaller than the lens OD. But it ain’t and I definitely can’t crimp it any further.
Three small dabs of clear epoxy and it should be good forever more…
It’s a simpler replacement for the digital thermometer, when continuous monitoring isn’t needed. I thought it’d be more durable, but … no.