When is "casefold" enabled as default?

[Bo Branten <bosse@xxxxxxxx>]

We have a compatibility problem with the ext4 feature "casefold" and now 
some users have reported that they have this feature enabled without 
asking so when formating the filesystem so I would like to as you if you 
know why this might happen? Does some distributions set it as default or 
is it some container system that has started using it?

Bo Branten