- Paths of C++-parsed files were not properly 'unixified' on Windows.
This was bad both for changes noisyness in PO files, and broke on
the un-escaping of `\n` and `\t` sequences.
- The `ProcessPoolExecutor` starts sub-processes differently on Linux
than on Windows or OSX. While Linux's `fork` keeps the same
environment (i.e. all Blender stuff remains available in workers
subprocesses), the 'spawn' used on Windows (and reportedly OSX) starts
a new bare python interpreter. This means that code executed by these
needs to be Blender-agnostic to be portable.
The only thing that is currently known broken on non-Linux platforms is
the RTL processing of some languages like Arabic or Hebrew.