Describe the issue:

if I append a masked array and something else using np.append, it returns a masked array but with the original mask replaced with False. I wouldn't mind if it returned a non-masked array (my fault!), but the current behaviour seems positively misleading! If it returns a masked array, it should surely preserve the mask.

Reproduce the code example:

import numpy as np
np.append(np.ma.masked_all(2),np.arange(2))

Error message:

No response

NumPy/Python version information:

1.20.3

Context for the issue:

No longer important for me (I corrected to np.ma.append), but could be misleading for others.