Red Hat Bugzilla – Bug 151628
Firefox should respect MOZ_ENABLE_PANGO
Last modified: 2007-11-30 17:11:02 EST
Description of problem:
Seems like currently Firefox startup script is setting MOZ_ENABLE_PANGO=1
unconditionally, which makes one unable to turn Firefox Pango support off.
A trivial fix is to simply not set MOZ_ENABLE_PANGO if it's already set.
Mozilla doesn't have this problem since it doesn't set MOZ_ENABLE_PANGO at all.
Version-Release number of selected component (if applicable):
BTW, I just noted that setting MOZ_ENABLE_PANGO in Firefox is against what is
advertised in FC3 release notes:
o Firefox and Mozilla can be enabled with pango rendering support,
which enables many text layout features, including the rendering
of CTL (Complex Text Layout) such as Indic languages. To enable
this, set the following environment variable when running Firefox
The problem is that the current Pango backend has serious
problems with Arabic, for example it hangs on some random pages, got
http://rira.ir/ for example.
Have you reported this pango + arabic hang in Bugzilla? This should go into a
Pango hang is awaiting in bug 151767. Another Pango+Arabic/Hebrew bug is being
worked at in Mozilla bugzilla:
So, while the hang is now known to be not Firefox specific, but the latter is
indeed a rendering problem with Pango Firefox. So I personally appreciate if
pango rendering is disable by default (it was enable on Feb 24). I've seen a
couple people so far complaining about update breaking their Firefox Persian
Well, with the newer firefox-1.0.2-1.3.1 it's even worse. Both firefox and
mozilla have pango backend selected at compile time and it cannot be turned off
using environment variables anymore :(. That means half of Persian/Arabic pages
cannot be rendered in FC3.
You can use MOZ_DISABLE_PANGO=1 now.
Thanks Mr. Aillon.
But Thunderbird still have pango enabled and doesn't listen to
MOZ_DISABLE_PANGO=1. So the arabic/persian/hebrew problem exicts on RSS feeds
and HTML mails yet.
I still believe the whole "on by default" is a bigger change than to fit FC3
updates. Moreover, I believe they all should keep respecting MOZ_ENABLE_PANGO,
though they are free to decide whatever if it's not defined. MOZ_DISABLE_PANGO
is not documented anywhere. MOZ_ENABLE_PANGO is in the release notes.