ls sort order

["Eric d'Alibut" <eric.halibut@gmail.com>]

I just noticed on a brand new install of testing that ls has begun to
sort alphabetically, but mixes uppercase and lowercase together i.e.
'Pearl' comes before 'pearl' but after 'otter'.

otter
Pearl
pearl

A stable Debian version I maintain behaves the good old-fashioned way:

Pearl
otter
pearl

Is this some utf-8 mutation?

--
No no no, my fish's name is Eric, Eric the fish. He's an halibut. I am
not a looney! Why should I be tarred with the epithet looney merely
because I have a pet halibut?