Handling file names in a case-insensitive way for Linux filesystems has been an ongoing discussion topic for many years. It is a (dubious) feature of filesystems for other operating systems (e.g. Android, Windows, macOS), but Linux has limited support for it. Over the last year or more, Gabriel Krisman Bertazi has been working on the problem for ext4, but it is a messy one to solve. He recently posted his latest patch set, which reflects some changes made at the behest of Linus Torvalds.