I had Mask_RCNN working and installed but my GPU was not being detected so I tried to use the newest version of tf for a new environment running python 3.8: pip install tensorflow scikit-image ...

Bug summary Once I type " import matplotlib.pyplot as plt" and run it, jupyter always returns： ＂Matplotlib is building the font cache; this may take a moment.＂ ＃Then the return messages will end up as ...