Experiment does not launch but runs

Hi

I recently upgraded to python 3.9. I can’t launch my experiment anymore. It says its running under stdout:
#Running
/path/to/myexperiment_lastrun.py

But I do not see the experiment. This is true even if my experiment has nothing but a ‘Hello World!’ textbox.

Do you know if things have changed with respect to python3.9? But more importantly, where can I see the reason why. No errors reported, a clean run but no window with the text.

OS (e.g. Win10): mac sierra
PsychoPy version (e.g. 1.84.x): don’t know
Standard Standalone? (y/n) If not then what?: custom built

I haven’t been using py3.9 yet. Not sure if it’s to do with that. Or the fact that you’re running macOS sierra (which I haven’t used in quite a few years now)

But you should be seeing output on the stdout. Hard to know what else to say from this level of information what is going wrong. Do demos run?

rolled back to an older version of python, concurrent with the latest that you are at.