A message with no HTML part showed as its text escaped, so a URL in it was only text: the pointer did not change over it and a click did nothing, while the same URL in an HTML message opened. Both backends now make a plain text body HTML through one function, html.fromText, which escapes it as before and makes the http, https, www., and mailto: addresses in it links, less the punctuation of the sentence around them and a closing parenthesis they did not open.