This package bundles a modified copy of gumbo-parser.
Being a modified copy it's possible to unbundle.

More details from the upstream maintainer:
    This is a customized version of gumbo built on top of on the following
    repository:

        https://github.com/vmg/gumbo-parser/tree/v1.0.0

    This repository has forked from the main repository to include memory
    improvements, and parser simplifications, speed improvements, and interface
    changes that allow simple editing of the tree post parsing.
    It has also been modified to supports the use of xhtml parsing rules (see
    the XMTML5 parsing comments in src/parser.c) and modified to recognize all
    svg and mathml tags in the tag enum.

    Due to recognizing a larger set of tags, we use our own version of
    tag_perf.h which is a variation of a minimal perfect hash function for our
    much larger set of tags.

    You can not simply replace this version of gumbo with the one from
    google/gumbo-parser without breaking Sigil.

Therefore, I'm leaving it as it is.

 -- Mattia Rizzolo <mattia@debian.org>
