Add an envvar restoring Qt 5 behavior for vertical font metricsHEADdev

As a last resort for users who have existing Qt 5 applications and
see differences in line metrics when porting to Qt 6, we introduce
an environment variable which lets them restore the old behavior
as a last resort.

This is primarily meant as a porting tool, since we do have other
tools, such as QFont::PreferTypoLineMetrics to work around issues
with fonts that by mistake do not explicitly set the
use-typo-metrics flag even if these are valid.

Pick-to: 6.8 6.9 6.10
Fixes: QTBUG-134602
Change-Id: Id1d7829888d55247d2f07ee0a49b91ff34f26889
Reviewed-by: Eirik Aavitsland <[email protected]>

0 files changed, 0 insertions, 0 deletions