The follow-up #966 left room for. With automatic kerning, horizontal type
with Proportional Metrics also applies `apkn`, and vertical type applies
`vkrn` and `vapk` along with `vpal`. Manual kerning turns them off, as it
turns off `kern`.
Vertical kerning used to cancel out: both top-to-bottom shapings had
harfrust's default `vkrn`. The baseline now has neither `vpal` nor the
kerning, so their difference carries both. A third shaping (`vpal` alone)
tells which advances `vpal` itself changed, and mojikumi steps aside only
for those. Vertical type without Proportional Metrics isn't kerned, as
before.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
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