Mozilla-firefox has a problem displaying some unicode characters from the rarer parts of character sets. The characters get displayed and disappear at random when selecting parts of text or moving other windows. I previously reported this problem to http://bugzilla.mozilla.org/show_bug.cgi?id=244437 where they suggested that distro giving incorrect library associations was at fault. Running ldd on mozilla-firefox-bin however doesn't give indication of any incorrect libraries.
Steps to Reproduce:
1. Open a page containing unicode characters, such as http://www.cogsci.ed.ac.uk/~richard/unicode-sample-3-2.html .
2. Select text, move windows around, scroll up and down...
3. Observe characters appearing and disappearing.
The actual problem here might reproduce rather by:
1. emerge mozilla-firefox
2. Check the libraries been linked.
The characters are not showing, or showing wrong, or at bad times; for more
complete description read the bug report at mozilla's bugzilla.
It is suggested that the actual results causing the problem to appear is wrong
Correct characters being shown all the time; which might be: correct library
linked to mozilla-firefox.
# emerge info
Portage 2.0.50-r6 (default-x86-1.4, gcc-3.3.3, glibc-2.3.3_pre20040207-r0, 2.6.4)
System uname: 2.6.4 i686 AMD Duron(tm) processor
Gentoo Base System version 1.4.12
distcc 2.12 i686-pc-linux-gnu (protocols 1 and 2) (default port 3632) [enabled]
CFLAGS="-march=athlon -pipe -fprefetch-loop-arrays -fstack-protector"
CONFIG_PROTECT="/etc /usr/X11R6/lib/X11/xkb /usr/kde/2/share/config
/usr/kde/3.1/share/config /usr/kde/3/share/config /usr/lib/mozilla/defaults/pref
/usr/share/texmf/tex/platex/config/ /usr/share/texmf/xdvi/ /var/qmail/control"
CONFIG_PROTECT_MASK="/etc/gconf /etc/terminfo /etc/env.d"
CXXFLAGS="-march=athlon -pipe -fprefetch-loop-arrays -fstack-protector"
FEATURES="autoaddcvs ccache distcc sandbox userpriv usersandbox"
USE="3dnow X Xaw3d aalib accessibility acpi acpi4linux aim alsa apache2 apm arts
avi berkdb bonobo cddb crypt cups curl dnd encode esd faad flac foomaticdb
freetype gb gcj gd gdbm gif gnome gpm gstreamer gtk gtk2 gtkhtml guile icq
imagemagick imlib ipv6 java joystick jpeg kde libg++ libwww mad mbox mikmod mmx
mng motif mozdomi mozilla moznomail mozp3p mozsvg mozxmlterm mpeg music mysql
ncurses net nls nptl offensive oggvorbis opengl oscar oss pam pdflib perl png
propolice python qt quicktime readline ruby samba scanner sdl slang spell sse
ssl stroke svg svga tcltk tcpd tetex theora tiff transcode truetype type1
unicode usb videos x86 xface xforms xinerama xml xml2 xmms xosd xprint xv xvid zlib"
I aint got this problem on my system:
root@Athena firefox-searches-en ldd /usr/lib/MozillaFirefox/firefox-bin
linux-gate.so.1 => (0xffffe000)
libmozjs.so => /usr/lib/MozillaFirefox/libmozjs.so (0x4003a000)
libxpcom.so => /usr/lib/MozillaFirefox/libxpcom.so (0x400ba000)
libplds4.so => /usr/lib/MozillaFirefox/libplds4.so (0x401b2000)
libplc4.so => /usr/lib/MozillaFirefox/libplc4.so (0x401b5000)
libnspr4.so => /usr/lib/MozillaFirefox/libnspr4.so (0x401ba000)
libpthread.so.0 => /lib/libpthread.so.0 (0x401ef000)
libdl.so.2 => /lib/libdl.so.2 (0x40200000)
libgtk-x11-2.0.so.0 => /usr/lib/libgtk-x11-2.0.so.0 (0x40203000)
libgdk-x11-2.0.so.0 => /usr/lib/libgdk-x11-2.0.so.0 (0x40521000)
libatk-1.0.so.0 => /usr/lib/libatk-1.0.so.0 (0x4059e000)
libgdk_pixbuf-2.0.so.0 => /usr/lib/libgdk_pixbuf-2.0.so.0 (0x405bc000)
libpangoxft-1.0.so.0 => /usr/lib/libpangoxft-1.0.so.0 (0x405d3000)
libpangox-1.0.so.0 => /usr/lib/libpangox-1.0.so.0 (0x405d9000)
libpango-1.0.so.0 => /usr/lib/libpango-1.0.so.0 (0x405e6000)
libgobject-2.0.so.0 => /usr/lib/libgobject-2.0.so.0 (0x40622000)
libgmodule-2.0.so.0 => /usr/lib/libgmodule-2.0.so.0 (0x40664000)
libglib-2.0.so.0 => /usr/lib/libglib-2.0.so.0 (0x40668000)
libm.so.6 => /lib/libm.so.6 (0x406f3000)
libstdc++.so.5 => /usr/lib/gcc-lib/i686-pc-linux-gnu/3.3.3/libstdc++.so.5 (0x40715000)
libgcc_s.so.1 => /usr/lib/gcc-lib/i686-pc-linux-gnu/3.3.3/libgcc_s.so.1 (0x40829000)
libc.so.6 => /lib/libc.so.6 (0x40834000)
/lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x40000000)
libX11.so.6 => /usr/X11R6/lib/libX11.so.6 (0x40945000)
libXrandr.so.2 => /usr/X11R6/lib/libXrandr.so.2 (0x40a13000)
libXi.so.6 => /usr/X11R6/lib/libXi.so.6 (0x40a17000)
libXinerama.so.1 => /usr/X11R6/lib/libXinerama.so.1 (0x40a1f000)
libXext.so.6 => /usr/X11R6/lib/libXext.so.6 (0x40a22000)
libXft.so.2 => /usr/X11R6/lib/libXft.so.2 (0x40a32000)
libfreetype.so.6 => /usr/lib/libfreetype.so.6 (0x40a46000)
libfontconfig.so.1 => /usr/lib/libfontconfig.so.1 (0x40ab9000)
libXcursor.so.1 => /usr/X11R6/lib/libXcursor.so.1 (0x40ae4000)
libXrender.so.1 => /usr/X11R6/lib/libXrender.so.1 (0x40aee000)
libpangoft2-1.0.so.0 => /usr/lib/libpangoft2-1.0.so.0 (0x40af6000)
libexpat.so.0 => /usr/lib/libexpat.so.0 (0x40b23000)
libz.so.1 => /lib/libz.so.1 (0x40b49000)
I have the exactly same set of libraries associated, but the bug does persist on firefox. Do you still see the bug I stated in the report at bugzilla.mozilla.org given in comment 0? (If you are missing the unicode characters in question altogether then you of course won't see the bug appearing at all).
If the bug does not appear on some machine, but instead all the characters get displayed in nice uniform manner, I'd like to figure out how to at least get my machine in that state.
What version of mozilla-firefox? That's a critically missing piece of information. Also what version of freetype do you have installed? Also what fonts are you using for display?
I have mozilla-firefox-1.0-r1 installed and don't see the problems you mentioned. I can select, scroll, etc. without problems.
Please re-open if you see this problem with the current (1.0-r1) firefox.
In my comment 0 I gave link to my mozilla's bugzilla report which gives some more information, such as the version numbers:
User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.6) Gecko/20040508 Firefox/0.8
Build Identifier: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.6) Gecko/20040508 Firefox/0.8
When a page containing unicode characters is loaded, some of the characters are
left undisplayed (ie. not even replacements displayed). However, when playing
with text selection all of these become visible, with that oddity that while
other characters in seltext area are white on gray blackground, these invisible
characters might or might not appear in black on gray blackground. Similarly if
I open some other window on top of Mozilla's window some of these characters
disappear and appear at random.
I'll attach two screenshots related, they aren't the best to demonstrate my
purpose but the problem is that taking of the screenshot using capture also
affects to displayed characters in a somewhat random manner.
Steps to Reproduce:
1. Open page http://www.cogsci.ed.ac.uk/~richard/unicode-sample-3-2.html
2. Scroll, select text, move around, change windows...
3. Watch the characters appear and disappear
The characters appear and disappear at random, with most common state being all
characters not showing.
Characters showing all the time.
Distribution is Gentoo, the package used is stable, compiled firefox, with
options gnome, gtk2, xinerama and truetype that might relate to problem.
The problem does still apply for 1.0-rc1, I'll try compiling 1.0-r1 today and reopen if the bug persists. The problem might be quite hard to spot as it does change with the set of fonts installed on machine, and also because the problem does appear in at least 3 forms:
* missing glyphs (remembering that xft, when actually missing a glyph should draw a box containing the unicode hex form)
* non-scaling, glyphs disappearing and appearing on window position change
* font's face color is black when selected instead of invert of selection color (of current theme, I think).
Freetypes tested range 2.1.5 to 2.1.9 patched.
Yes, it does seem to exist with mozilla-firefox-1.0-r2 too. I took two more screenshots if they are required, it appears that latin extended additional is best code block to test this bug, most of the others are contained in common unicode fonts. Of course if you use modern thai(?) or transcribed indian you might have whole latin extended already installed as well.
Of course this bug doesn't actually work with truly missing glyphs, only those which are missing on some fonts but exist on others (perhaps scalable vs. bitmap fonts?).
A-ha, with updated version of x server to xorg-6.7.0-r1 I see yet another form of borkage with the glyphs, this time it triggers on selecting and dragging-and-dropping, interesting.
Reopen if this is still an issue with up-to-date versions...
Hasn't appeared to me in Deer Park, however I've seen complaints from other people that this bug has appeared to them in Deer Park while previously having been ineffective, so I'm not sure. As far as I'm concerned this can be closed anyways.