message: doc: Set PYTHONUTF8=1 for functional tests on Windows
diff: @@ -26,13 +26,20 @@ See [/doc/fuzzing.md](/doc/fuzzing.md)
  ### Functional tests
  -#### Dependencies
  +#### Dependencies and prerequisites
  The ZMQ functional test requires a python ZMQ library. To install it:
  - on Unix, run `sudo apt-get install python3-zmq`
  - on mac OS, run `pip3 install pyzmq`
  +
  +On Windows the `PYTHONUTF8` environment variable must be set to 1:
  +
  +```cmd
  +set PYTHONUTF8=1
  +```
  +
  #### Running the tests
  Individual tests can be run by directly calling the test script, e.g.:
  