
AdBlock Plus’s effect on Firefox’s memory usage - harshal
https://blog.mozilla.org/nnethercote/2014/05/14/adblock-pluss-effect-on-firefoxs-memory-usage/
======
gorhill
It's not just memory overhead, it is also CPU overhead.

One approach is to write the filtering engine from scratch. It is what I did,
without looking at ABP's code beforehand in order to ensure a clean slate
mind.

I didn't get it right the first time, I did spend _quite a large amount of
time_ benchmarking, measuring, prototyping, etc.

Once I was satisfied I had finally had a solid code base, I went and
benchmarked it against ABP to find out how it compared:

[https://github.com/gorhill/httpswitchboard/wiki/Net-
request-...](https://github.com/gorhill/httpswitchboard/wiki/Net-request-
filtering:-overview#abp-filtering)

And for HTTPSB's numbers, keep in mind there were an _extra over 50,000 rules_
in the matrix filtering engine (something not found in ABP).

So I think this shows clearly ABP's code can be improved.

~~~
sspiff
As far as I can tell, HTTPSB is not available for Firefox, please fix!

I would love to use something better than ABP (in terms of performance, it
does content filtering just fine), but I'm not so desperate to abandon the
(warning: subjective content ahead) greatest browser of all times to lower the
memory footprint of an ad blocker.

~~~
idlewan
I'm betting this is not an easy task.

It however would be really awesome for HTTPSB (which I just installed on
chromium and fallen in love instantly with) to be ported to firefox.

Seeing all the privacy-related features treated, by domain/site/everywhere
rules, being able to block separately js/plugins/cookies (and by the way, the
matrix is a great idea, a lot more useable than anything else out there)... in
one extension only. Great work already, gorhill!

~~~
Justsignedup
Eh it has some default behavior quirks. Like being unable to log into
arstechnica.com because it won't let that cookie get stored.

~~~
gorhill
Whitelist the "cookie" cell in the matrix, save with one click on the padlock.
Now cookies will be allowed everywhere by default (except for those
ubiquitously blacklisted hostnames).

------
neals
The first thing people complain about with browsers is probably memory usage.
I doubt that many people actually understand what a browser actually does with
that memory. I sure don't.

100mb sounds like a lot of memory for a webpage. Where does all this memory go
to?

~~~
nnethercote
Many people think of a browser as a tool for displaying text and pictures,
with maybe a bit of JS code and some CSS effects on the side. That was true in
the late 90s, but these days a browser is actually a fully-fledged programming
environment that also happens to have some incredibly sophisticated multimedia
capabilities: text, images, video, audio, animations, 3d graphics, etc.

The most popular websites run quite amazing amounts of code, and JavaScript
execution is usually the dominant consumer of memory.

If you want a deeper understanding, visit about:memory in Firefox you'll get a
detailed breakdown of how memory is used.

~~~
nfoz
> That was true in the late 90s, but these days a browser is actually a fully-
> fledged programming environment that also happens to have some incredibly
> sophisticated multimedia capabilities: text, images, video, audio,
> animations, 3d graphics, etc.

Maybe I just miss the 90s, but I would _much_ rather have the simple content
browser than a "full-fledged programming environment", especially since all of
that content is coming from the random untrusted intarwebs. Anyone want to
write a browser engine that skips all the modern BS and just does a good job
delivering mostly-static webpages?

~~~
astrobe_
Your best bet is text-based browsers: Lynx, Elinks, or mayve Emacs/W3M. On
simple sites like HN, they are more or less usable.

I also sometimes wish the Web were just serving data in an easily processable
format, and let the user decide what and how they are presented. Of course
this would definitely and completely defeat the ads-supported scheme on which
sits Internet. An ads-free Web would probably require the resources (media
files, services, storage space, bandwidth, etc.) to be massively distributed
among the PCs of the end-user, who are already paying for bandwidth,
processing power and storage anyway. But it would also be quite inefficient as
it would require equally massive fault tolerance.

~~~
DanBC
> I also sometimes wish the Web were just serving data in an easily
> processable format, and let the user decide what and how they are presented.

It's really sad that many people feel this is the state of the modern www. The
original intention - you serve me stuff with suggestions about presentation,
but my client software and OS and hardware can do what it likes with that
stuff - appears to be long dead.

> Of course this would definitely and completely defeat the ads-supported
> scheme on which sits Internet. An ads-free Web would probably require the
> resources (media files, services, storage space, bandwidth, etc.) to be
> massively distributed among the PCs of the end-user, who are already paying
> for bandwidth, processing power and storage anyway. But it would also be
> quite inefficient as it would require equally massive fault tolerance.

I do not use ad blockers. I view ads. If I really like the site and trust
their ad network I will click relevant links.

But I loathe the way some websites and apps work. Facebook on iOS opens all
links in the facebook app. Apps and websites decide they will not let my zoom
or rotate.

Especially hateful are the ads which take me out of a Chrome (iOS) session to
open the app store. I contact owners of sites with those ads and politely tell
them what happens, and then I cut and padte the URL to a list of sites that I
will never ever visit again. This is as bad as the smiley ads that yell "
HELLO!! ".

Advertisers seem reluctant to realise that irritating people like me ( ad
tolerant) is a rwally bad move and is the reason so many peopke use ad
blockers.

~~~
test1235
>Advertisers seem reluctant to realise that irritating people like me ( ad
tolerant) is a rwally bad move and is the reason so many peopke use ad
blockers.

You're a tiny, tiny percent of users who actively chooses to view ads. Not to
be insulting, but advertisers don't care what you think - the money they lose
from your custom isn't worth the effort to make the change.

I don't bother blocking ads and I've never felt the need to install anything.

But the day I come across a site which I deem annoying enough, you can bet I
won't hesitate for a second, and that'll just blanket block everything. As
long as the advertisers play nice, I don't particularly mind. I don't care to
differentiate between 'good' and 'bad' advertisers - just like how I'm not
worth their time, neither are they worth mine.

------
dcc1
[http://someonewhocares.org/hosts/zero/](http://someonewhocares.org/hosts/zero/)

~~~
bru
I switched from ABP to this hosts file a few months ago and I have zero
regret. My browser's faster, lighter and ads are blocked just as well as with
ABP.

I actually even started splitting my hosts file: the layout is

    
    
        /etc/hosts                ('compiled' version)
        /etc/hosts.d/
        /etc/hosts.d/aaa-warning  (warning reminding me to run `update-hosts` instead of modifying /etc/hosts. Appears atop the compiled file)
        /etc/hosts.d/adblock      (that website's hosts file)
        /etc/hosts.d/base         (original system hosts file)
        /etc/hosts.d/dolead       (work-related file for development)
    

And I have the following functions in my .bashrc file:

    
    
        function update-hosts() {
            cat /etc/hosts.d/* > /etc/hosts;
        }
    
        function update-adblock() {
            curl http://someonewhocares.org/hosts/zero/hosts -o /etc/hosts.d/adblock 2> /dev/null
            update-hosts
        }
    

So if I want to update "adblock" (it is obviously an improper name) I simply
do `sudo update-adblock` and if I change another file (mostly
`/etc/hosts.d/dolead`) I'll just run `sudo update-hosts`.

Works wonders.

~~~
TarpitCarnivore
Have you been able to block stuff like Tynt, and other copy/paste triggered JS
stuff?

~~~
bru
I was not aware of Tynt, but I believe it's well blocked.

I just looked at the adblock-hosts file, and 'tynt' appears several times. One
of those lines is commented with a link to an article about tynt[0]. I tried
copy-pasting from The New Yorker and TechCrunch (who, as claimed by the author
of the article, use tynt), and both times there was no crap appended.

0:
[http://daringfireball.net/2010/05/tynt_copy_paste_jerks](http://daringfireball.net/2010/05/tynt_copy_paste_jerks)

~~~
TarpitCarnivore
Thanks, I may try this out and see if I can move over my few custom blocked
sites that implement this stuff.

------
maaaats
> _Many people (including me!) will be happy with this trade-off — they will
> gladly use extra memory in order to block ads._

Well, for me the whole point of blocking ads is because they are often big
flash things that hog cpu and memory. If ABP is no better, then most of the
reason is gone. I'd actually like to view ads to support more sites.

~~~
baby
the point for me is the visual noise, not the memory that ads consume.
Actually, normal users are used to the lag, they don't see it as much as we
do. You can take a look at consoles that have run games at 30fps for decades
and nobody complained.

~~~
mschuster91
I don't care about the "visual noise" of normal/banner-type ads - the real
problem are those fucking layer ads with confusing icons (the X is the left
one, the maximize button the right one), so if you want to read the content,
first find out which type of layer ad it is, try to spot the 2x2px hotzone for
the close button and THEN read the content.

People install adblockers because too many idiots became too fucking greedy
and ruined ads for everyone else!

~~~
orclev
Exactly, they had their chance, and they abused the privilege, so now we've
taken it away.

~~~
wutbrodo
Tell me about it man; I found that food was getting kind of expensive at some
of the restaurants I frequented so now I just dine-and-dash, several times a
week. Restaurants as a whole had their chance to charge me for food, they
abused it, so I took that right away.

/s

~~~
simoncarter
I can’t figure out if you’re making a sarcastic point in rebuttal against
orclev, or, because the analogy is so bad, taking the piss out of people who
would use that analogy.

------
mullingitover
This is like a commercial for forking Firefox to build highly efficient ad
blocking into the browser.

It's sad that the most-demanded feature on every browser, as evidenced by
plugin downloads, is ad blocking. However, all the major browsers are produced
by companies with their hands in advertising, and this conflict of interest
has resulted in this feature request going unfulfilled for a over a decade.

Fork 'em.

~~~
DenisM
I don't think we can block ads in mainstream browsers because ad providers
will just work around the blocks. Plugins provide defense in numbers against
suck workarounds, making ad blocks actually effective.

~~~
__david__
This doesn't make sense to me. Why can't ad providers work around the blocks
in adblock? And why could they work around those same blocks if they happened
to be integrated into the browser itself?

Take popup blocking as an example. That's integrated into the browser and has
almost completely eliminated the annoying popup ad.

~~~
pbhjpbhj
>Why can't ad providers work around the blocks in adblock? //

It's not really a work _around_ but some sites do block your [full] access and
say to turn off your adblocker if you want access to the [additional] content.

That said I don't think it makes much difference to the matter at hand.

------
chrismorgan
I would like to see a lighter blocking list—one that _doesn’t_ try to be
absolutely comprehensive, but just focuses on the 95% of ads that can be fixed
at 10% of the cost (actually I think it’d be more like 99% at 0.1% of the
cost).

~~~
Groxx
I've been using this on my Android phone (but have not audited it, I should
really do that some time): [https://addons.mozilla.org/en-
US/firefox/addon/bluhell-firew...](https://addons.mozilla.org/en-
US/firefox/addon/bluhell-firewall/)

ABP has a huge page-load slowdown on my phone, this is essentially
unnoticeable, and still removes the vast majority that I encounter.

------
bithush
My primary computer is a laptop from 2008 with a 2.5Ghz Core 2 Duo and other
than a 1 second delay in startup I don't notice any performance degradation in
general use compared to running without ABP.

Currently this machine has been up for 3 days and 17 hours and Firefox has
been running the whole time and it is using 303MB with 4 tabs open one of
which is the Daily Mail (don't judge!) which is an extremely busy page. This
is perfectly acceptable in my opinion. I only have 4GB RAM which by todays
standards in not much either. Obviously reducing the memory footprint is great
but I can't say it has ever been a problem I have ever noticed.

On a side note the past few updates to Firefox have improved performance a
lot. I am really impressed by how much quicker the browser is, especially with
Chrome seeming to just get slower and slower with each update.

~~~
probably_wrong
> I only have 4GB RAM

I've also seen this in some other comment, so I think it's worth pointing out:
if you have a _desktop_ computer then yes, it's ok. However, there are also
netbooks and notebooks around with _a lot_ less memory than that. Tablets,
while not currently one of Firefox markets, are also commonly seen with less
than that. Lots of parents with second-hand computers, too, which haven't been
touched in a while because it "just works".

The overall attitude towards hardware is apparently "use it for two years,
then throw away and get a new one", and yet underpowered computers surround me
in a 5:1 ratio. I sometimes have to install plain old versions of software
(Office '97 comes to mind) because the new ones provide 5% new features at the
cost of half your memory.

Maybe everyone else has techie friends that only care about the latest and
shiniest, or maybe the rest of the world is rich enough to throw away
perfectly good hardware just because they feel like it. But from _my_
experience (as biased as it is), 4Gb is _not_ an "only" situation.

~~~
icebraining
In my experience, Firefox uses less memory on systems with less RAM. My laptop
only has 2Gb, and Firefox runs fine, even if on my work laptop it can reach
2.5Gb.

And I'm not shy about using tabs either, I often have many dozens open.

------
graylights
Some sites have tried gimmicks to block adblock users. I wonder now if they'll
make thousands of empty iframes.

~~~
artursapek
Heh, not sure slowing down your own site for a reason unknown to most visitors
is going to help your bottom line.

~~~
Silhouette
At the risk of stating the obvious, if your site is ad-funded then annoying
users who don't see your ads so they go away and don't come back is a win. If
they bitch about it to their friends who also wouldn't see your ads and those
friends don't visit in the first place, it is an even bigger win.

~~~
Omniusaspirer
I'm not so sure this is "obvious". It presumes that those people will never
refer anyone who would watch your ads, and also that search engines won't down
rank you in results based on the number of people bailing from your site
instantly/avoiding clicking on it.

~~~
aranjedeath
If you've bought into the lexicon of marketing it is. They're stealing revenue
from you.

If you haven't, you're an asshole and you're fucking your users for no reason
at all (ads are no reason).

------
BorisMelnik
I'm just gonna say this as a person who uses ABP and has not done any low
level memory analysis: browsing using ABP saves me much more time and makes my
browsing much quicker:

-ads take so long to load and when ABP is not enabled bogs down my browser hard core

-when watching videos I have to wait 3-20 seconds for them to load, with ABP enabled I do not have to wait at all

It consistently saves me several minutes every day. If it adds a few extra
milliseconds to load some style sheets I have never, ever noticed.

------
SixSigma
I would recommend Privoxy rather than adblock. I chose it because it can be
used with any browser rather than needing to be a plugin and have had great
results with it. As a bonus I have it running on a virtual server and use an
ssh tunnel on any system I end up using. This gets me round filters and
installing things other than ssh. So if I am using my Android phone on free
wifi, I know I'm not being dns hijacked or under HTTP MITM attack.

[http://www.privoxy.org/](http://www.privoxy.org/)

~~~
mixedbit
A drawback is that a proxy won't be able to filter HTTPS traffic.

~~~
Silhouette
That depends on the proxy. Systems that effectively MITM your own network's
traffic have been around for some years now. All you need for outbound
connections is to install an additional certificate in your browser so the
proxy can act a trusted partner for HTTPS.

I don't know whether anyone has made such a proxy for use in the kind of
situation we're talking about here, however.

~~~
ethana
Adguard does that. Been beta testing it. One adblock to rule them all kinda
thing.

------
axx
It's 2014.

My computer has 12 Gigabytes of RAM.

I don't give a shit, as long as i don't have to view those terrible stupid
Ads.

Advertisers, fix your practises and i will view your Ads again.

~~~
raverbashing
One of the best ad-blockers is actually called FlashBlock (not sure this is
the name today)

It will remove around 90% of obnoxiousness...

~~~
VoxPelli
Or you just go to Tools > Addons > Plugins and chose to have Firefox ask you
before it activates the Flash plugin for a page – same functionality I think?

~~~
raverbashing
Good, looks like it's a new feature.

Yeah, this would be more or less the same functionality (FlashBlock makes it
per item, so you can, for example see a video but not activate the other
elements)

~~~
wutbrodo
I think the Firefox plugin option does this too (at least, it works that way
in Chrome). You can activate a plugin (and only that plugin) by clicking on
it.

------
bambax
Wouldn't the solution involve allowing plugins to manipulate the content of a
page before it is parsed by the browser?

There used to be a proxy adblocker that did that, but I don't think it works
anymore.

The Kindle browser uses a proxy to pre-render pages on the server in order to
lighten the load of the device.

Could AaaS (Adblock as a service) be a viable business? I think I'd pay for
it.

~~~
Cthulhu_
> Could AaaS (Adblock as a service) be a viable business? I think I'd pay for
> it.

It probably could, however I'm sure it would be shut down quickly by
advertisers and parties showing ads - after all, you're offering a service to
remove their source of income. Unless you'd funnel part of your subscriber's
income back to the advertisers, based on whose ads you block. But I'm sure
it'd end up being too expensive for the consumer and too much of a hassle for
the one offering the service.

Not to mention you'd force your users to funnel all of their internet traffic
through your servers, and it wouldn't work with encrypted pages (which large
parts of the internet is moving towards)

~~~
__david__
> It probably could, however I'm sure it would be shut down quickly by
> advertisers and parties showing ads

What legal leg would they have to stand on? There's no law that prevents me
ripping out the ads of magazines that get delivered to me…

~~~
TheLoneWolfling
The same one that allows them to sue people for scraping their website.

Tech laws are absurd.

------
ladzoppelin
Use Bluhell Firewall and NoScript for Firefox instead of ABP.
[https://addons.mozilla.org/en-US/firefox/addon/bluhell-
firew...](https://addons.mozilla.org/en-US/firefox/addon/bluhell-
firewall/?src=ss)

~~~
column
also don't forget to set noscript.firstRunRedirection to false after
installing NoScript to prevent it from opening its homepage after every
update.

------
nclark
i would rather have my browser crash and never open again for the rest of my
life than not use adblock. take all the memory, CPU, fuck it GPU that you
want, you fantastic addon.

------
SudoNick
I think this is the fourth or fifth time, in recent memory, that I've seen
someone from Mozilla criticize Adblock Plus and call on its developers to make
changes. ABP startup time and memory consumption were subjects I recall, and
its general impact on page load times may have been as well.

I can understand Mozilla taking some interest in how addons behave, and
constructive feedback on extensions is a good thing. However, ABP is the type
of extension that is likely to have issues in those areas because of what it
does. Which is very important to users, especially those who rely upon it for
its privacy and security enhancing capabilities. It is those users who should
decide whether the performance and resource usage trade-offs are acceptable.
Mozilla shouldn't make, or try to make, such decisions.

The situation with ABP 2.6 ([https://adblockplus.org/development-
builds/faster-firefox-st...](https://adblockplus.org/development-
builds/faster-firefox-startup),
[https://adblockplus.org/forum/viewtopic.php?t=22906](https://adblockplus.org/forum/viewtopic.php?t=22906))
might not be a case of this, but that along with the wider pattern of platform
developers being more controlling, does make me somewhat concerned about
Mozilla taking too much interest in extensions. I hope my worries are for
naught.

~~~
nnethercote
I'm the author of the post. I was extremely careful to keep the tone of the
post neutral. This paragraph sums it up:

> So, it’s clear that ABP greatly increases Firefox’s memory usage. Now, this
> isn’t all bad. Many people (including me!) will be happy with this trade-off
> — they will gladly use extra memory in order to block ads. But if you’re
> using a low-end machine without much memory, you might have different
> priorities.

If you think this post is unreasonable, I think your skin is too thin.

~~~
SudoNick
I noticed that you said that, and expected others to notice as well. I don't
really think your post unreasonable. I'm just a little concerned that, even in
a case of pure intentions and desire for balance, extension developers may
feel pressured to make changes and end up sacrificing features or
effectiveness.

Did you notice how some people here, and at your blog, proposed modifications
what would trade coverage for memory consumption? Even if that would result in
_known_ filter hits being eliminated, and also without qualifying that if such
an approach were adopted it should be preference based?

------
demi_alucard
For those who do not know, there is an EasyList without element hiding rules.

[https://easylist-
downloads.adblockplus.org/easylist_noelemhi...](https://easylist-
downloads.adblockplus.org/easylist_noelemhide.txt)

With these rules firefox's memory usage only goes up from 290MB to 412MB,
instead of 1.5GB for the website mentioned in the article for me.

The downside is that this list has a more limited coverage than the full
version of the list.

------
spain
Another (related) popular extension that I've noticed negatively affecting
Firefox's performance is HTTPS Everywhere.

~~~
gcp
HTTPS Everywhere is mostly annoying because it stops random sites from
working, and people generally forget to check that it's HTTPS Everywhere
that's causing it.

------
ColbieBryan
Editing hosts files, installing Privoxy or Glimmerblocker, using Ghostery,
Bluhell Firewall - I've tried all of these suggestions and unfortunately ABP
is the only way to go if blocking all unwanted pop-up's is a priority.

------
alipang
Anyone knows if this also affects Chrome? I have Chrome saying Adblock is
using 126MB of memory, but if there are giant stylesheets injected elsewhere
that might no be reported fully in the Chrome task manager.

~~~
gerbal
As a chromebook user (with 2gb of ram) Adblock plus is routinely the chief
culprit for slow downs. I've found it using 400mb of ram with sites like
youtube and facebook open.

------
dbbolton
If you are on a low-end machine and can't afford a larger memory footprint,
you should probably be using a lighter browser in the first place, but if you
really want to use Firefox and block ads, one option is to just block them
through your hosts file, then the addon becomes largely unnecessary.

[http://someonewhocares.org/hosts/](http://someonewhocares.org/hosts/)

[http://winhelp2002.mvps.org/hosts.htm](http://winhelp2002.mvps.org/hosts.htm)

------
caiob
I'd love to hear the side-effects of using Disconnect.

------
nhebb
I'm surprised AdBlock is so popular. I tried it a few years ago and noticed
the sluggishness immediately. I know it's not a feasible alternative in
everyone's opinion, but if you're running a low end machine and want to block
the most pernicious ads (flash, multiple external javascript, etc.) then
Firefox + NoScript is the way to go.

~~~
svantana
The killer feature of ABP is: no Youtube ads. Is there any other way to
achieve that?

~~~
bru
`/etc/hosts`-blocking the ads works fine for youtube. See the list at
[http://someonewhocares.org/hosts/zero/](http://someonewhocares.org/hosts/zero/)

~~~
allyant
Doesn't block them here.

------
Vanayad
Same issue appears in chrome as well. Got the site they linked to ~ 2.4GB
before the browser stopped responding.

------
hbbio
Very interesting.

There might be an architecture problem here. Another solution is to use a
proxy to block ads, like GlimmerBlocker for OSX. But I didn't investigate
memory usage, though I tend to think it will be lower (plus have the added
benefit of working simultaneously for all browsers).

~~~
andreasvc
A proxy cannot dynamically interact with the DOM, so it cannot do everything a
plugin can. I think the solution is to use better datastructures in the plugin
and improve the integratation of the plugin with the browser.

~~~
psykovsky
Cloudflare can, somehow...

~~~
andreasvc
Probably using Javascript, i.e., same mechanism as AdBlock Plus.

------
kmfrk
I use the program Ad Muncher for Windows, and I've found that it sometimes
becomes a humongous bandwidth hog, when I'm watching video.

So it's not just memory that can be at risk of hogging.

~~~
octo_t
are you sure its Ad Muncher using bandwidth and not, you know, the _video_
you're watching?

~~~
kmfrk
Sure. Windows's bandwidth monitor tells me as much - and closing Ad Muncher
fixes the slog.

------
sdfjkl
On the other hand AdBlock (edge of course, not the co-opted plus), saves quite
a bit of network traffic. Nice if you're on metered (or slow) internet.

------
linux_devil
I switched from Firefox to Safari , when I found out 900 Mb used by firefox on
my machine , now I know the real reason behind that .

~~~
nnethercote
That's a surprising story from a user named "linux_devil"!

Maybe it's time to try switching back?

------
chrismcb
Did I read that correctly? One website had 400 iframes? FOUR HUNDRED? Not 4,
but 4 HUNDRED? Surely there is a better way.

------
mwexler
Ah, 3 words that always seem to show up together: firefox and memory and
usage. I look forward to when I see that 4th word, "minimal", in there as
well. Yes, I know original post is about an addin increasing memory usage, but
I guess that doesn't surprise me anymore either, sadly, when thinking of
firefox.

Even with the memory pain, I still (mostly) love FF.

~~~
nnethercote
It's much better than it used to be. For example, Firefox 15 made a class of
very common leaks caused by add-ons impossible. Firefox 26 massively reduced
the amount of memory used on image-heavy pages. And there have been _many_
smaller improvements over the past three years, under the aegis of the
MemShrink project
([https://wiki.mozilla.org/Performance/MemShrink](https://wiki.mozilla.org/Performance/MemShrink)).

------
Shorel
My browser is fast again!

Thank you, really thank you.

------
hokkos
LastPass is victim of the same fate.

~~~
kijin
LastPass is bearable if you disable all the DOM-modifying options, such as
highlighting and adding pretty icons to input fields. Instead I use keyboard
shortcuts to select the login info to use.

------
vladtaltos
if 19 million people use it, why hasn't it become a feature firefox offers
itself ? doesn't this mean people want some option of blocking ads ? I'm
guessing this a native-integrated version will require a lot less memory...

------
nly
So is there any insight as to why? My guess, without looking at the code would
be the regex engine allocating millions of NFA graphs.

~~~
nnethercote
Nope.
[https://bugzilla.mozilla.org/show_bug.cgi?id=988266#c20](https://bugzilla.mozilla.org/show_bug.cgi?id=988266#c20)
has a detailed breakdown of the style-sets memory usage.

------
Donzo
You guys: you've got to stop using this.

You're missing important messages from sponsors.

