The latest release of MRIcroGL for macOS (v1.2.20211006) transitions from using the system Python 2.7 to a statically linked Python 3.7. This is in response to deprecation of Python 2.7 and Apple's requests that applications should not use the system Python. Some users have reported that scripting no longer works, though using previous versions works. Best guess is that this reflects people upgrading where the old installation set the PyLib preference to Python 2.7.
The latest release of MRIcroGL for macOS (v1.2.20211006) transitions from using the system Python 2.7 to a statically linked Python 3.7. This is in response to deprecation of Python 2.7 and Apple's requests that applications should not use the system Python. Some users have reported that scripting no longer works, though using previous versions works. Best guess is that this reflects people upgrading where the old installation set the PyLib preference to Python 2.7.
-rargument from the terminal to reset the preferences resolve the issue? e.g./Applications/MRIcroGL.app/Contents/MacOS/MRIcroGL -r