⁢ rendered as an unknown character

[Jitse Niesen]

Configuration: Linux, Debian testing, Firefox 1.0.4 (but upgrading to
1.0.6did not help)

The MathML entities ⁡ and ⁢ (short for ApplyFunction and
InvisibleTimes) are rendered as an unknown character (a square with the
number 2061 or 2062 in it; those number are the Unicode positions for the
characters). See e.g. the following URL for an example:
http://www.w3.org/Math/testsuite/testsuite/Presentation/TokenElements/mo/mo6.xml

I do have the Mathematica and tex fonts installed (I also have Adobe's
Symbol font, but using that gives more problems and does not solve the
current problem). However, ⁡ and ⁢ are unprintable characters, so
presumably they are not in a font.

Strangely, it works fine on another computer, running Fedora Core 2 and
Firefox 1.0.6. My problem is that I have no idea where to start looking:
Could it be a problem with Firefox, the fonts, the X server, the font server
(I'm using fontconfig)? I guess that installing more fonts does not help,
since there is no glyph associated to ⁢. On both the Debian and the
Fedora box, gucharmap recognizes 0x2061 and 0x2062 as unprintable
characters.

I already asked a question about this on MozillaZine (see
http://forums.mozillazine.org/viewtopic.php?t=304513 ), but I did not get an
answer.

Any help would be much appreciated.
Cheers, Jitse Niesen

[Roger B. Sidje]

These invisible characters have baffled many people (see previous
thread(s) to that effect). They have been fixed through the patch on bug
306543. The problem is that they are not handled well by all the font
subsystems on all platforms. So the idea is to deal with them in the
MathML renderer itself (by ignoring/fitering them and not letting them
reach the font subsystems).
---
RBS

https://bugzilla.mozilla.org/show_bug.cgi?id=306543

Post by Jitse Niesen
Configuration: Linux, Debian testing, Firefox 1.0.4 (but upgrading to
1.0.6 did not help)
The MathML entities ⁡ and ⁢ (short for ApplyFunction and
InvisibleTimes) are rendered as an unknown character (a square with the
number 2061 or 2062 in it; those number are the Unicode positions for
http://www.w3.org/Math/testsuite/testsuite/Presentation/TokenElements/mo/mo6.xml
I do have the Mathematica and tex fonts installed (I also have Adobe's
Symbol font, but using that gives more problems and does not solve the
current problem). However, ⁡ and ⁢ are unprintable characters, so
presumably they are not in a font.
Strangely, it works fine on another computer, running Fedora Core 2 and
Could it be a problem with Firefox, the fonts, the X server, the font
server (I'm using fontconfig)? I guess that installing more fonts does
not help, since there is no glyph associated to ⁢. On both the Debian
and the Fedora box, gucharmap recognizes 0x2061 and 0x2062 as
unprintable characters.
I already asked a question about this on MozillaZine (see
http://forums.mozillazine.org/viewtopic.php?t=304513 ), but I did not
get an answer.
Any help would be much appreciated.
Cheers, Jitse Niesen