[WinCairo] fonts/use-typo-metrics-1.html is failing as ImageOnlyFailure It seems that GetOutlineTextMetrics doesn't preserve OS/2 USE_TYPO_METRICS flag for OpenType fonts. fonts/lineheight5000-typolineheight2300.woff seems a WOFF generated from a OpenType font. If I convert lineheight5000-typolineheight2300.woff to TTF, and converted back to WOFF, the test case will pass. Firefox seems using HarfBuzz to get OS/2 section on Windows.
I wonder if the tools you use to convert to TTF and WOFF again might do extra sanitisation changes. Are you able to use the script to generate a TTF and then load directly the .ttf file with @font-face rule?
I created lineheight5000-typolineheight2300.ttf. I confirmed USE_TYPO_METRICS flag is preserved, the test can pass. diff --git a/mathml/tools/use-typo-lineheight.py b/mathml/tools/use-typo-lineheight.py index 9768979f48..c98020868b 100644 --- a/mathml/tools/use-typo-lineheight.py +++ b/mathml/tools/use-typo-lineheight.py @@ -44,7 +44,7 @@ font.os2_windescent_add = False font.os2_use_typo_metrics = True -path = "../../fonts/math/lineheight%d-typolineheight%d.woff" % (winHeight, typoLineHeight) +path = "../../fonts/math/lineheight%d-typolineheight%d.ttf" % (winHeight, typoLineHeight) print("Generating %s..." % path, end="") font.generate(path) if font.validate() == 0: