Philipp Stephani <p.stephani2@gmail.com> schrieb am Mi., 30. Nov. 2016 um 00:09 Uhr:

That url-retrieve breaks in this case is unfortunate, but I guess we can't do much about it without breaking other stuff.

Ah, I guess the URL functions could simply call string-to-unibyte, that should do the right thing in all cases.