Hello,

I was wondering why Iceweasel displays some pages in very ugly way -
some glyphs were sharp, others were somewhat fuzzy and different
size/weight.

It turned out that

 - the page selects Tahoma as the preferred font
 - wine installs a Tahoma font
 - the Tahoma from wine has some (extended) Latin glyphs present only as
   outlines, not bitmaps
 - bitmaps are used for the Lating glyphs that have them, outlines
   otherwise

This could be prevented if fontconfig pruned the bitmaps for ranges that
are incomplete. eg in this case the font has some glyphs in Basic Latin
and Extended Latin *, and some of the glyphs in Extended Latin * are
present only as outlines. As all the Latin ranges are supposed to work
together bitmaps should be turned off for the Latin ranges so that all
the glyphs are rendered the same. I am not sure how glyphs like 'fi' fit
into this, though.

If fontconfig cannot affect what font features are used by applications
then perhaps this should be handled by freetype/pango/whatever does
that. Still fontconfig is supposed to be a central place for these kinds
of settings. It would be ugly to do separately in every toolkit.

Thanks

Michal