Makes them hard to read.
It seems to be caused by a combination of
word-break: break-all; property and injecting non-breaking spaces instead of regular spaces when the word separator is a space (i.e., when the “Word separator” field is either blank or set to a space).
I don’t know what happens under the hood on mobile and desktop apps, but the visual result is the same.
I can understand that
word-break: break-all; is needed for passwords because they might not contain line break opportunities like spaces and hyphens, but passphrases should really use
Also, I don’t know if there’s some valid reason to use NBSP instead of regular spaces, but it seems like a really bad idea. Chrome, at least, copies them literally when you manually highlight and copy the text from the interface.