Comment 7 for bug 1851880

I suspect the regression is from:

commit 35c8d64f98074d7604d4cc97e145efa086064cd8 (refs/bisect/bad)
Date: Mon Oct 21 19:03:54 2019 +0100

    Add super- and subscript support to Eeschema.

    Note that since the markup might exist for other reasons, it has
    to be turned on with a preference setting. (It goes through a set
    of bitflags so the same architecture can be used for other markup
    structures that we might want to support in the future.)

    Note also that this is more about engineering nomenclature than
    visual formatting. In that respect it's more similar to overbar
    than italic or bold.