plain external links get prefixed with ????

[Joachim Mairböck]

Plain external links (using just a URL, e.g. ​https://example.com/) get prefixed with some quesion mark signs in the PDF output.

Wiki Text of the test page:

= Test page for PDF output

Link: https://example.com/

Longer link: https://subdomain.example.com/this/is/a/long/link

Sometimes, the links get even multiple ? signs, but I couldn't reproduce that with this test page.