Issue with using certain Image Quality metrics downstream

I’m having an issue trying to flag some problematic images in my pipeline based on the MeasureImageQuality correlation measurement. In FlagImage when I try to so a bunch of the parameter settings just disappear once I select correlation and an image (see image below). I encounter this error in both 3.1.5 and 3.1.8 but not if I go back to 2.2.0 (the second image shows the same view in 2.2.0 to show what the GUI should be showing)


It also happens if trying to use these images in other modules like ImageMath so it’s not specific to the FlagImage module. It also happens with the LocalFocusScore measurement but nothing else that I checked.

When this happens, there’s an error icon shown on the pipeline instead of the eye. If I hover over it the error is:
“Exception in cpmodule.test_valid ‘ascii’ codec can’t decode byte 0xff in position 0: ordinal not in range(128)”

Seems like a bug but wanted to check I’m not missing something stupid or that it’s not just a problem