Thanks @tim, this works, but in my opinion is somewhat inconvenient.
That’s because it creates a separate run/debug configuration that PyCharm does not associate with the relevant script (in your example streamlit_app.py). Thus, when right-clicking streamlit_app.py in PyCharm’s file explorer the run/debug options there do not invoke streamlit correctly.
I can get around this by starting streamlit from within Python, via the bootstrap hack, although I understand that this not supported and has some issues.
Overall, I think it would be great if there was an official way of invoking streamlit from within python.