Bug#601241: iceweasel: Animated gifs flashing instead of animating

[Mahesh T. Pai]

Package: iceweasel
Version: 3.6.11-1
Severity: normal


Example page:-

http://www.gifs.net/gif/index.php3?n=subcat_images.php3&id=37&start=0&end=20&cat_name=Dolphins_and_Whales

This happens with gifs on other sites too, so this 
is not site specific, Above is a random link I looked
up from google.

I find that the gif images are flashing, instead of 
displaying the proper animation.

Same GIFs render ok on chromium here. 

Info about Chromium:-

Chromium	6.0.472.62 (Developer Build 59676) Built on Debian unstable, running on Debian squeeze/sid
WebKit	534.3
V8	2.2.24
User Agent	Mozilla/5.0 (X11; U; Linux x86_64; en-US) AppleWebKit/534.3 (KHTML, like Gecko) Chrome/6.0.472.62 Safari/534.3
Command Line	 /usr/lib/chromium-browser/chromium-browser






-- Package-specific info:

-- Extensions information
Name: Adblock Plus
Location: /usr/share/mozilla/extensions/{ec8030f7-c20a-464f-9b0e-13a3a9e97384}/{d10d0bf8-f5b5-c8b4-a8b2-2b9879e08c5d}
Package: xul-ext-adblock-plus
Status: enabled

Name: Default
Location: /usr/lib/iceweasel/extensions/{972ce4c6-7e08-4474-a285-3208198ce6fd}
Package: iceweasel
Status: enabled

Name: Tab Mix Plus
Location: /usr/share/mozilla/extensions/{ec8030f7-c20a-464f-9b0e-13a3a9e97384}/{dc572301-7619-498c-a57d-39143191b318}
Package: xul-ext-tabmixplus
Status: enabled

-- Plugins information
Name: Shockwave Flash
Location: /usr/lib/flashplayer-mozilla/libflashplayer.so
Package: flashplayer-mozilla
Status: enabled


-- Addons package information
ii  flashplayer-mo 3:10.2.d161-0. Macromedia Flash Player
ii  iceweasel      3.6.11-1       Web browser based on Firefox
ii  xul-ext-adbloc 1.2.2-1        Advertisement blocking extension for web bro
ii  xul-ext-tabmix 0.3.8.3-1      adds dozens of new capabilities to tabbed br

-- System Information:
Debian Release: squeeze/sid
  APT prefers testing
  APT policy: (500, 'testing'), (1, 'experimental')
Architecture: amd64 (x86_64)

Kernel: Linux 2.6.35-trunk-amd64 (SMP w/1 CPU core)
Locale: LANG=en_IN, LC_CTYPE=en_IN (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages iceweasel depends on:
ii  debianutils                   3.4        Miscellaneous utilities specific t
ii  fontconfig                    2.8.0-2.1  generic font configuration library
ii  libc6                         2.11.2-6   Embedded GNU C Library: Shared lib
ii  libglib2.0-0                  2.27.0-1   The GLib library of C routines
ii  libgtk2.0-0                   2.22.0-1   The GTK+ graphical user interface 
ii  libnspr4-0d                   4.8.6-1    NetScape Portable Runtime Library
ii  libstdc++6                    4.5.1-9    The GNU Standard C++ Library v3
ii  procps                        1:3.2.8-9  /proc file system utilities
ii  xulrunner-1.9.2               1.9.2.11-1 XUL + XPCOM application runner

iceweasel recommends no packages.

Versions of packages iceweasel suggests:
ii  libgssapi-krb5-2            1.8.3+dfsg-2 MIT Kerberos runtime libraries - k
pn  mozplugger                  <none>       (no description available)
pn  ttf-lyx | latex-xft-fonts   <none>       (no description available)
pn  ttf-mathematica4.1          <none>       (no description available)
pn  xfonts-mathml               <none>       (no description available)
pn  xprint                      <none>       (no description available)

Versions of packages xulrunner-1.9.2 depends on:
ii  libasound2               1.0.23-2        shared library for ALSA applicatio
ii  libatk1.0-0              1.30.0-1        The ATK accessibility toolkit
ii  libbz2-1.0               1.0.5-6         high-quality block-sorting file co
ii  libc6                    2.11.2-6        Embedded GNU C Library: Shared lib
ii  libcairo2                1.9.14-1        The Cairo 2D vector graphics libra
ii  libdbus-1-3              1.4.0-1         simple interprocess messaging syst
ii  libevent-1.4-2           1.4.13-stable-1 An asynchronous event notification
ii  libffi5                  3.0.9-3         Foreign Function Interface library
ii  libfontconfig1           2.8.0-2.1       generic font configuration library
ii  libfreetype6             2.4.2-1         FreeType 2 font engine, shared lib
ii  libgcc1                  1:4.5.1-9       GCC support library
ii  libglib2.0-0             2.27.0-1        The GLib library of C routines
ii  libgtk2.0-0              2.22.0-1        The GTK+ graphical user interface 
ii  libhunspell-1.2-0        1.2.11-1        spell checker and morphological an
ii  libjpeg62                6b1-1           The Independent JPEG Group's JPEG 
ii  libmozjs3d               1.9.2.11-1      The Mozilla SpiderMonkey JavaScrip
ii  libnspr4-0d              4.8.6-1         NetScape Portable Runtime Library
ii  libnss3-1d               3.12.8-1        Network Security Service libraries
ii  libpango1.0-0            1.28.1-1        Layout and rendering of internatio
ii  libpixman-1-0            0.18.4-1        pixel-manipulation library for X a
ii  libpng12-0               1.2.44-1        PNG library - runtime
ii  libreadline6             6.1-3           GNU readline and history libraries
ii  libsqlite3-0             3.7.2-1         SQLite 3 shared library
ii  libstartup-notification0 0.10-1          library for program launch feedbac
ii  libstdc++6               4.5.1-9         The GNU Standard C++ Library v3
ii  libx11-6                 2:1.3.3-3       X11 client-side library
ii  libxrender1              1:0.9.6-1       X Rendering Extension client libra
ii  libxt6                   1:1.0.7-1       X11 toolkit intrinsics library
ii  zlib1g                   1:1.2.5.dfsg-1  compression library - runtime

-- no debconf information