First of all thanks for putting this project together.

I am currently using Asciidoctor to write all the posts for my website. However, I use custom made extensions to render my posts according to my specifications.

Unfortunately, Hugo comes with a hard coded pre-specificed list of allowed Asciidoctor extensions. When Hugo is preparing the Asciidoctor converter it basically checks whether the passed extension is on the list of allowed extension and if not it simply ignores the extension.

I have created a fork that simply removes the check and Hugo is able to use any arbitrary Asciidoctor extension which means I can render my website just by calling hugo.

This behavior is quite puzzling to me as I do not see any reason to not allow the user to determine the extensions which he/she wants to use. Of course, It should be the final user's responsibility to ensure that her/his desired extension is compatible with Hugo. I might be missing something here.Would it be possible to turn off this check on allowed extensions? Is there any reason otherwise.

Thanks again for developing this awesome software.