I found this but I have not tried it myself :
===
In order to install the version 5.1 you need to add additionals DEB repository
to your APT’s config.
For instance append those two new repository to your /etc/apt/sources.list
files:
deb
Fixed with 1.9~rc1+nobinonly-0ubuntu1~8.04.2 in hardy and 1.9~rc1
+nobinonly-0ubuntu1 in intrepid as my code has been checked in upstream
in rc1.
** Changed in: xulrunner-1.9 (Ubuntu)
Status: New = Fix Released
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Firefox 3 proxy auto config (PAC) reload button does not work
The patch has been checked in upstream.
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Firefox 3 proxy auto config (PAC) reload button does not work
https://bugs.launchpad.net/bugs/225520
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Backports Testing Team, which is subscribed to Gutsy Backports.
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** Also affects: gutsy-backports
Importance: Undecided
Status: New
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Firefox 3 proxy auto config (PAC) reload button does not work
https://bugs.launchpad.net/bugs/225520
You received this bug notification because you are a member of Ubuntu
Backports Testing Team, which is subscribed