Default fonts in Firefox

[Ian Jackson]

Ian Jackson writes ("Default fonts in Firefox"):
> Bug 7196 complains that the fonts in Firefox are ugly.

So, we've had some discussion and it seems that we've established
that (in the situations where the results change):

 * In hoary, fontconfig would select a font with the wrong metrics;
   as I understand it this will cause some documents to be printed
   incorrectly.

 * In breezy, fontconfig selects a font with the right metrics;
   unfortunately, this font looks bad on the screen in firefox.

For printing (and similer typesetting applications) it is of course
important to have a font with the right metrics.  Whereas on the web
it may be nice to have exactly the right metrics, but it is much more
important to pick a font that looks good. [1]

I've not heard any suggestion yet as to whether there is a sane way to
get fontconfig to distinguish these two cases.  That is, as to whether
it is possible to arrange for a different fontconfig configuration,
depending on whether we prefer a font that looks good, or one that has
the same metrics as the specified font.  If that were possible then we
could provide appropriate configuration for fontconfig that would be
correct in each case.

It's also clear to me that I don't understand how this whole font
system works anyway.  In particular, I don't understand how the
machinery in Firefox turns the CSS from the webpage plus the user's
preferences into a request to fontconfig.

We need to know the answer to these questions.  If you know how to do
this, or have an idea, please let me know.

If I can't figure out how to do the right thing then we have to
consider configuring fontconfig to always prefer to use the
good-looking fonts, instead of using the ones with the right metrics.
This would be bad for printing but firefox is probably more important.
See [2] below.

Thanks,
Ian.

[1] I am not interested in any more assertions that it is vitally
important for braindead web designers' nightmare sites to have the
right metrics.  The sites that are braindead in that way are vastly
outnumbered by the sites which look worse because of the less
good-looking font.  So please do not argue this point.

[2] I've had representations that the answer is to delete
<!--
  URW provides metric and shape compatible fonts for these 3 Adobe families.
  -->
        <alias>
          <family>Times</family>
          <accept><family>Nimbus Roman No9 L</family></accept>
and the next two aliases from fonts.conf.