I forgot you can see what locale Geany thinks its in by looking at `Help->Debug Messages` which should say something like:
``` Geany INFO : Geany 1.39 (git >= b7558417), en_AU.UTF-8 ```
Note LC_ALL environment variable is a convenience to override all the other variables with its value, it does not need to be set if all the other variables are set. Geany calls `setlocale(LC_ALL, "")` as required to set the various locale categories according to [precedence order defined in 8.2 here](https://pubs.opengroup.org/onlinepubs/007904875/basedefs/xbd_chap08.html#tag...)
Python site.py changed in 3.10 to explicitly use your LC_CTYPE value to read `.pth` files, so maybe it uses LC_ALL in 3.6 and so assumes ASCII when its not set.