From Newsgroup: nz.comp

Did you know that the Linux ext4 filesystem has the option for
case-insensitive file/directory names?

First of all, ensure your kernel was built with the rCLCONFIG_UNICODE=yrCY option. Then, you have to enable this option at filesystem creation
time, by specifying an rCLencodingrCY setting, e.g.

mkfs -t ext4 -E encoding=utf8 -2block-device-+

Next, you mount the volume as normal, but there is no difference in behaviour--yet. You must enable case-insensitivity on the directories
on that volume where you want it (before putting anything in those directories):

chattr +F -2dirname-+

This attribute is propagated by default when subdirectories are
created in that directory, so if you want to enable it for the whole
volume, you can set it on the root directory of the volume while it is
still empty.
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