
The Acid3 Test (2008) - aylmao
http://acid3.acidtests.org/
======
rhcom2
"Acid3, in particular, contains some controversial tests and no longer
reflects the consensus of the Web standards it purports to test, especially
when it comes to issues affecting mobile browsers. The tests remain available
for historical purposes and for use by browser vendors. It would be
inappropriate, however, to use them as part of a certification process,
especially for mobile browsers."

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

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jcranmer
For people who don't follow modern web standards, a modern web browser getting
100/100 is actually failing tests. You should get 97/100, failing tests 23,
25, and 35.

The site itself is no longer maintained and updated to reflect changes to
standards.

~~~
drc0
care to explain why?

~~~
jcranmer
If you're asking specifically why the test isn't being maintained, I can
somewhat speak to that.

The first Acid test was a relatively simple test that could visually
demonstrate if browsers implemented CSS. When IE became the dominant browser,
Microsoft essentially stopped all development on IE. At the time, IE had a
very broken implementation of CSS (although, it should be noted, IE6 was the
best implementation of CSS _when it came out_ , as everybody else was just as
bad). The Acid2 test was created in large measure specifically to goad IE into
improving its standard compliance (mostly on CSS). As a result of the
publicity of the Acid2 test, the other browsers fixed their engines to pass
Acid2, which put pressure on IE to fix their engine.

Since it had been effective in pushing browsers to implement the CSS2 standard
correctly, the author turned to creating Acid3 to push browsers to implement
more technologies. Whereas Acid1 and Acid2 were largely about CSS layout,
Acid3 focuses more on testing JS API implementations. Acid3 was heavily
criticized for letting browsers score well just by having a very thin, minimal
surface implementation of the feature instead of testing thorough correctness,
as well as for being very opinionated in pushing browsers to implement
specific technologies (SVG fonts being the big one).

By the time Acid3 came out, there was already a change in the development of
web browsers. Microsoft was once again participating in the standards
compliance process and trying to drive their browser to modern compliance, so
all of the major browser vendors were very active in discussion about
implementation. Also, the W3C changed its specification process to rely more
heavily on having a thorough compliance testsuite that had two passing
independent implementations before a standard could be considered finalized.
The CSS2.1 testsuite wasn't complete at the time these tests were developed,
but has now come out, with almost 10,000 individual tests in them, far more
thorough than any of the Acid tests could claim to be.

Since the Acid tests no longer had value in being the most comprehensive tests
of their underlying functionality, nor in compelling browser developers to be
competitive in standards support, their developer stopped working on the
project. Indeed, since Acid3 fails at even being a comprehensive test for what
it tests, its author publicly stated that he isn't interested in updating it
when specifications update.

~~~
Sniffnoy
Do you know what changed regarding 23, 25, and 35, and why it was at the time
considered correct to pass them, but now considered correct to fail them?

~~~
kevindong
You can see details by loading the test page and then clicking on the 'A' of
'Acid3'.

~~~
ehsankia
That's not super helpful, for example 25 just says "wrong exception". The
original commenter seemed to know exactly why these 3 specific tests were
failing, I'm also curious what specific specs changed that are no longer true.

------
sonofgod
On my machine:

Chromium 71: 97%, blocks 2&3 silver, pauses at 24, 64.

Firefox Quantum 64: 97%, blocks 2&3 silver, pauses at 24, 64, 65.

From Wikipedia:

Bucket 2: DOM2 Core and DOM Events

Bucket 3: DOM2 Views, DOM 2 Style, CSS3 selectors and Media Queries

By April 2017, the updated specifications had diverged from the test such that
the latest versions of Google Chrome and Mozilla Firefox no longer pass the
test as written. Hickson acknowledges that some aspects of the test were
controversial and has written that the test "no longer reflects the consensus
of the Web standards it purports to test, especially when it comes to issues
affecting mobile browsers."

~~~
msla
As I recall, the Firefox of the time didn't pass Acid3, either, and there was
a minor controversy over the fact they changed the test in a way that made it
friendlier to Firefox:

[https://en.wikipedia.org/wiki/Acid3](https://en.wikipedia.org/wiki/Acid3)

> Initially, Firefox 4 scored 97/100, because it did not support SVG fonts.
> Later, Firefox 4 scored 100/100, because the SVG font tests were removed
> from Acid3.

> According to Mozilla employee Robert O'Callahan, Firefox did not support SVG
> fonts because Mozilla considered WOFF a superior alternative to SVG
> fonts.[29] Another Mozilla engineer, Boris Zbarsky, claimed that the subset
> of the specification implemented in Webkit and Opera gives no benefits to
> web authors or users over WOFF, and he asserted that implementing SVG Fonts
> fully in a web browser is hard because it was "not designed with integration
> with HTML in mind".[30]

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arendtio
Sounds like it is time for Acid4. After all, those test did a great job at
showing browser incompatibilities.

~~~
Analemma_
There’s html5test.com and css3test.com

~~~
jenscow
The google bot scored 45% on css2test.com.

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jimrandomh
Acid2 is currently not passing either in Chrome (71.0.3578.98). I'm surprised
these never got turned into automated unit tests.

~~~
aboutruby
From Wikipedia: "The test fails when browsers become compliant with current
CSS collapse and margin standards."

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azhenley
> Modern web browsers don't 71 pass the Acid3 test anymore

What does it mean by "71 pass"?

~~~
wutbrodo
The test is scored out of 100, so presumably it means getting a 71+ score

~~~
metalliqaz
My understanding with these kinds of tests is that the only passing grade is
100/100

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pilom
[http://acid3.acidtests.org/support-a.png](http://acid3.acidtests.org/support-a.png)
is a resource that page attempts to load that 404's now. I'm guessing that's
part of the reason it doesn't score 100%. Not the browser's fault.

~~~
sp332
It loads fine for me. Looks like this
[https://imgur.com/a/lrTMBmE](https://imgur.com/a/lrTMBmE)

~~~
simlevesque
If you wget the file you'll see this:

\--2019-01-18 13:46:40--
[http://acid3.acidtests.org/support-a.png](http://acid3.acidtests.org/support-a.png)

Resolving acid3.acidtests.org (acid3.acidtests.org)... 75.119.197.251

Connecting to acid3.acidtests.org (acid3.acidtests.org)|75.119.197.251|:80...
connected.

HTTP request sent, awaiting response... 404 Not Found

2019-01-18 13:46:40 ERROR 404: Not Found.

~~~
sonofgod
This is by design. By the specs, browsers should not display a favicon if the
file 404s. But that file contains a valid favicon, so rendering it is a
failure. [source: Wikipedia]

------
aylmao
I bumped into the acid3 test, and I noticed it didn't pass in Chrome anymore.
Would anyone have any context as to why this is? It's a little bit odd to me
that backwards compatibility was broken in at least 3 ways here.

~~~
jcranmer
Acid3 was not updated when people decided to change the specifications. There
are 3 things that are known to fail. Two of them are related to one change
(see
[https://github.com/whatwg/dom/issues/319#issuecomment-296345...](https://github.com/whatwg/dom/issues/319#issuecomment-296345763)
for details on that change). The third test is one where Acid3 mandates
something that every browser did but was wrong per the specification, and it
took several years for people to notice (see
[https://bugzilla.mozilla.org/show_bug.cgi?id=1311329](https://bugzilla.mozilla.org/show_bug.cgi?id=1311329)
for some more details).

The Acid3 test on that website is officially unmaintained:
[https://lists.w3.org/Archives/Public/www-
archive/2017Jul/000...](https://lists.w3.org/Archives/Public/www-
archive/2017Jul/0003.html)

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chobytes
98/100 in Safari for me.

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zerohp
Fails the back button test.

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nkkollaw
Chrome is still 97/100, but honestly that's a pretty old test and things have
changed.

Someone remembers XHTML..?

~~~
metalliqaz
Also getting 97 with Firefox.

~~~
aylmao
Safari is at 98, which I guess now means slightly worse.

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Corrado
Has it really been 10+ years since the "acid" tests debuted? I can remember
when these things were the height of the browser wars. I guess I should be
glad that we don't really need them anymore.

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dstroot
Latest Chrome: 97% IE 11: 100%

Acid3: FAIL

------
x0n
Internet Explorer 11 .... 100/100 !!

~~~
floatingatoll
Quirks or strict mode?

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qubex
Current Safari Mobile gets 98/100

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omouse
66/100 on Firefox and after a pause it shoots up to 96/100! 97/100 on Brave.

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dwighttk
Safari Version 12.0.2 (14606.3.4) 98/100

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kords
Microsoft Edge gets 100/100

