asciidoctor/asciidoctor-backends — pull request #88 by jirutka (2014-10-19 13:58:56+00:00)
Title: Replace form checkbox with unicode symbols in html5/block_ulist

Looks better and it’s also already used in the built-in version of the backend ([here](https://github.com/asciidoctor/asciidoctor/blob/v1.5.1/lib/asciidoctor/converter/html5.rb#L851-L852)).