[ERROR]: Could not use confusing filename (Invalid byte sequence in conversion input)

When importing files with non-English characters (notably æ, ø, å) to an Ardour session, I get the error in the title. I’m on official Ardour 8.11 on Linux Mint Debian Edition 6.

The import manager fails to preview these files, but they can be imported and behaves as expected in the session. The files in question are created using Ardour 8.11 on the same machine (Session > Export).

I think Ardour should be able to handle special characters. Anyone have an idea where to start looking?

Edit: I prefer using Ardour (and Linux) with English interface, though I need it to be aware of and able to read Norwegian characters. So not trying any translations.

locale:


LANG=en_US.UTF-8
LANGUAGE=en_US
LC_CTYPE="en_US.UTF-8"
LC_NUMERIC=nb_NO.UTF-8
LC_TIME=nb_NO.UTF-8
LC_COLLATE="en_US.UTF-8"
LC_MONETARY=nb_NO.UTF-8
LC_MESSAGES="en_US.UTF-8"
LC_PAPER=nb_NO.UTF-8
LC_NAME=nb_NO.UTF-8
LC_ADDRESS=nb_NO.UTF-8
LC_TELEPHONE=nb_NO.UTF-8
LC_MEASUREMENT=nb_NO.UTF-8
LC_IDENTIFICATION=nb_NO.UTF-8
LC_ALL=