(I orignally posted this question in "Using Swift", since I discovered it in the REPL, but then I learned that it's based on LLDB, and LLDB has the same behavior: Swift REPL UTF-8 keyboard support)
I'm using LLDB from Windows with Docker WSL2 via the docker image swiftlang/swift:nightly-5.5, which is a Linux image. I run Docker with these options: --security-opt seccomp=unconfined -it --rm --name swift -e 'LC_ALL=C.UTF-8' /bin/bash
This is run from Windows 10 1903, Windows Terminal with local code page 65001, although the code page doesn't make a difference.
The environment variable setting in the docker run line means that e.g. danish characters (æ, ø, å) work correctly in the launched bash, i.e. I can cat them into files and such. They do not, however, work in LLDB (or the Swift REPL).
Instead these characters are either completely ignored and lead to no input whatsoever, or they lead to strange things being output such as cursor movement or "\U+00F8", the character code for one of those letters. It's not a problem to read files containing UTF-8, using <filename, or to print such characters correctly. It's just not possible to input them.
Is this a know issue or limitation? Is it related to Linux, or perhaps Docker, perhaps when run from Windows? Thanks in advance 