#1121823 firefox-esr: Why install /etc/firefox-esr/firefox-esr.js when firefox try to read from /etc/firefox

Package:
firefox-esr
Source:
firefox-esr
Description:
Mozilla Firefox web browser - Extended Support Release (ESR)
Submitter:
Simone Piccardi
Date:
2025-12-03 10:47:02 UTC
Severity:
normal
#1121823#5
Date:
2025-12-03 10:45:17 UTC
From:
To:
Dear Maintainer,

I got a serious mislead when trying to setup some firefox system wide
preference because I saw this package installing the file
/etc/firefox-esr/firefox-esr.js so I assumed that that was used.

But stracing firefox to try to uderstand why configurations were not applied
with:

strace -e file firefox  2> strace.out

an then searching with:

grep "/etc/fir" strace.out

gave me as result:

openat(AT_FDCWD, "/etc/firefox/defaults/pref", O_RDONLY|O_NONBLOCK|O_CLOEXEC|O_DIRECTORY) = -1 ENOENT (No such file or directory)
access("/etc/firefox/policies/policies.json", F_OK) = 0
openat(AT_FDCWD, "/etc/firefox/policies/policies.json", O_RDONLY) = 40

I did this on Debian stable, but the same apply to current testing and
unstable.

So /etc/firefox-esr/firefox-esr.js is never read, and I do not understand why
you are installing it in the package and what its meaning is.

From what see the right place for such a confuration should be the
/etc/firefox/defaults/pref directory.