Support for multiple variants

[luca-vercelli]

AFAIK, weasyprint "--variant" parameter allows a single value.

However it is possible that a PDF supports multiple standards, for example PDF/A and PDF/UA. See e.g. pdfa.org

Could this be supported?

[liZe]

Hi!

That could be possible to mix some of the variants, but adding the feature is not as simple as allowing multiple --variant values.