#680095 iceweasel: Iceweasel consumes 50-80% cpu when idling

Package:
iceweasel
Source:
firefox-esr
Submitter:
Jerry Quinn
Date:
2025-09-18 07:31:25 UTC
Severity:
normal
#680095#5
Date:
2012-07-03 12:37:11 UTC
From:
To:
Dear Maintainer,

I've seen this behavior in both iceweasel 12 and 13.  My normal browser has 60
tabs open.  When not doing anything, iceweasel consume 80% CPU.  Firing up a
clean profile and no tabs open still consumes 50% or more CPU.  Disablig all extensions and plugins doesn't change this at all.
#680095#10
Date:
2012-07-21 05:28:39 UTC
From:
To:
I see this behavior with Iceweasel 10.0.5 from wheezy as well. I'm
up-to-date as of right now, and starting with "iceweasel -safe-mode"
with one tab open consumes ~120% CPU (dual core macmini 3,1 with 8GiB
RAM).

I started noticing this "recently", which isn't to say it hasn't been
happening for a while but I usually have two running in two different
X sessions with somewhere around 120 tabs open and it has been pretty
unresponsive lately.

Any more information that would be useful?
#680095#15
Date:
2012-10-30 10:12:05 UTC
From:
To:
Dear Maintainer,

Testing user here.
I confirm iceweasel's growth of CPU hunger these last months.
And even up to some seconds freeze.
I don't remember when it begun, may be spring 2012 ?
I have 15~20 windows each with 2 to 15 tabs.
The iceweasel process takes 60% to 75% CPU (sometimes even more).
I mean when I do nothing with it, being elsewhere (xterm, reportbug...)
Chromium and Epiphany are OK (with much fewer tabs).
When I run (deprecated)iceowl too they compete for CPU.

Could it be a problem with their shared XULRUNNER or JSthing or so ?

Very few extensions and very few active ones.
This CPU consumption is a PAIN : low battery life, high fan noise,
unresponsiveness.

Thanks for the packaging work, good luck to squash the bugs.

P. M.
#680095#20
Date:
2012-10-30 16:36:22 UTC
From:
To:
Some more information to track the issue:
After hibernate and re"boot" it seems the CPU usage cools down OK.

P. M.
#680095#25
Date:
2012-12-07 13:53:01 UTC
From:
To:
Dear Maintainer,

iceweasel stills uses ~70% CPU when idleing according to "top".
Even after hibernate-defreeze.
The cooling fan noise is a pain. I wonder how other Debian users do ? Any clue
to help me ?
Thanks in advance.

P.M.
#680095#30
Date:
2012-12-09 19:26:25 UTC
From:
To:
Hello dear Maintainer,

hopefully here is something more :
After some hibernate-defreeze cycles (or days?) the CPU consumption is back to
normal.
I hope this helps diagnose the issue.

Have fun debianing

Pierre M.
#680095#35
Date:
2012-12-11 15:31:55 UTC
From:
To:
Dear Maintainer,

good news : the CPU consumption seems to have disappeared. Now iceweasel-
firefox does not even show in "top" listing when not used.
May be a result from several updates these last days : moz and/or js and/or xul
and/or xorg and/or whoknows.

Thanks for the packaging work.

Pierre M.
#680095#40
Date:
2013-06-23 20:32:10 UTC
From:
To:
Dear Maintainer,

I have good news : after software updates, restarts, reboots, release and so
the problem was still there and amplifying with hibernate-resume cycles ; but
thanks to LWN.net I read a comment that pointed to Firebug ; I disabled Firebug
and restarted iceweasel and Yeah! now iceweasel is very low on the CPU radar.
Issue gone for me :-)
I suggest reaffecting the bug to Firebug.

Pierre M.
#680095#45
Date:
2021-04-30 01:28:43 UTC
From:
To:
Je ne m'attendais pas à ce que cela fonctionne. http://turr4.confirmceiling.work/apmix



Pierre Morin✅
#680095#50
Date:
2021-06-04 06:04:21 UTC
From:
To:
Vous ne devriez pas le manquer! https://bit.ly/3peWbZ0



 Pierre Morin📧
#680095#55
Date:
2022-09-13 13:20:24 UTC
From:
To:
https://bit.ly/3RH3u9o
#680095#60
Date:
2024-10-16 12:32:06 UTC
From:
To:
https://t.co/l7JH4AXvdo
#680095#65
Date:
2025-09-18 07:29:21 UTC
From:
To:
src:iceweasel has been superseded by src:firefox-esr in version
45.0esr-1 in March 2016. Transitional packages to ease upgrades were
provided in the wheezy, jessie, stretch and buster releases. The
transitional packages have been removed finally before the bullseye
release in August 2021.
After regular security support for buster ended in August 2022 and LTS
support ended in June 2024, I'm closing the remaining bug reports now.

Andreas