[deanm (Dean)]

Ice can persist through a full heat-shield re-entry (if in the right place).

One of the Shuttles once landed with a large icicle still present outside, up behind the flight deck - a leaking valve shedding water.

SpaceX's 1st stage doesn't do a full heat-shield re-entry (it's still sub-orbital) and the propulsive burns to bring it back are brief, with sustained firing of the centre engine only just before touchdown - by which stage previously-accumulated ice could prevent proper leg deployment & locking.

Dean
It just ocurred to me: SpaceX need to borrow from the astro community.

What they need is a bunch of dew straps/heaters to avoid ice formation where critical!