Unclear error when displaying images from arrays of float dtype in notebook #5116

import numpy as np
from PIL.Image import fromarray
fromarray(np.random.random((30, 30)))

---------------------------------------------------------------------------
KeyError                                  Traceback (most recent call last)
~\Miniconda3\envs\py\lib\site-packages\PIL\PngImagePlugin.py in _save(im, fp, filename, chunk, save_all)
   1219     try:
-> 1220         rawmode, mode = _OUTMODES[mode]
   1221     except KeyError as e:

KeyError: 'F'

The above exception was the direct cause of the following exception:

OSError                                   Traceback (most recent call last)
~\Miniconda3\envs\py\lib\site-packages\IPython\core\formatters.py in __call__(self, obj)
    343             method = get_real_method(obj, self.print_method)
    344             if method is not None:
--> 345                 return method()
    346             return None
    347         else:

~\Miniconda3\envs\py\lib\site-packages\PIL\Image.py in _repr_png_(self)
    671         """
    672         b = io.BytesIO()
--> 673         self.save(b, "PNG")
    674         return b.getvalue()
    675 

~\Miniconda3\envs\py\lib\site-packages\PIL\Image.py in save(self, fp, format, **params)
   2149 
   2150         try:
-> 2151             save_handler(self, fp, filename)
   2152         finally:
   2153             # do what we can to clean up

~\Miniconda3\envs\py\lib\site-packages\PIL\PngImagePlugin.py in _save(im, fp, filename, chunk, save_all)
   1220         rawmode, mode = _OUTMODES[mode]
   1221     except KeyError as e:
-> 1222         raise OSError(f"cannot write mode {mode} as PNG") from e
   1223 
   1224     #

OSError: cannot write mode F as PNG