Martin Robinson | 24 Apr 01:39 2015

Clarifying 3D feature defines

In the process of cleaning up and dusting off the GTK+ cmake build
system, we have rediscovered the pair of somewhat confusing feature
defines WTF_USE_3D_GRAPHICS and ENABLE_3D_RENDERING. From a brief
audit, it appears that WTF_USE_3D_GRAPHICS is a generic flag for any
kind of 3D rendering at all (including WebGL), while
ENABLE_3D_RENDERING refers specifically to perspective

Would it be worthwhile to clarify these flags slightly? My proposal is
ENABLE_PERSPECTIVE_TRANSFORMS, though I support any names that reduce
the possible confusion between these flags.

Martin Robinson | 23 Apr 20:12 2015

Proposal: Remove TextureMapperImageBuffer

Background: There currently exists a fallback TextureMapper
implementation that does not use OpenGL to composite and project
layers, but instead relies on 2D rasterization. This does not work
correctly for Cairo, since Cairo only supports affine transformations.
I believe this path is only used by GTK+ (and perhaps WinCairo) now.

Proposal: I would like to remove TextureMapperImageBuffer and make
TextureMapperGL the only implementation of TextureMapper. Not only
will this simplify the code, it will remove a build flag
(TEXTURE_MAPPER_GL). The current path isn't (or really shouldn't) be
enabled by default.

Please speak up if you are opposed. :)

Yoav Weiss | 23 Apr 09:48 2015

Client Hints


As I've discussed during my session at the contributor's meetup, I'm interested in implementing Client-Hints in WebKit.

For those unfamiliar with it, Client-Hints is a standard destined to improve content negotiation, and enable the browser to advertise various characteristics to the server along with resource requests, so that the server can adapt its responses to these characteristics in a cache friendly way.

It was conceived to enable and facilitate server-side based responsive images solutions. The main use-cases for that are automatic optimization of legacy Web content, where it's not always easy to go back and modify the HTML, as well as external image optimization solutions that prefer content negotiation over HTML modification.

I'd like to emphasize that this effort is orthogonal to the <picture> effort. (and the use-cases covered by each are orthogonal as well)

Since I intend to go ahead with implementation soon, I wanted to share my intentions with the wider WebKit community and gather feedback at this early stage.

Cheers :)
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Chris Dumez | 22 Apr 00:39 2015

[Proposal] Remove support for 'multipart/x-mixed-replace' main resources


I would like to suggest we remove support for 'multipart/x-mixed-replace’ main resources while keeping support for multipart images.

Based on Chrome usage data, this feature is extremely rarely used by Web sites (less than 0.00001% of page loads) [1]. This feature adds complexity to the loader and is a source of (security) bugs (e.g. [2] recently), current support also seems buggy.

Current support in Safari / WebKit:
- Support is not great is WebKit. If you load a Motion JPEG main resource for example, it will keep creating a new ImageDocument and all its DOM tree for every frame (tested on Safari / Mac).
- It looks like support is broken on Safari on iOS (I tried a Motion JPEG main resource on iOS8, I see the first frame then a blank page that never finishes loading).

Other browsers:
- Never supported by IE (including IE11) for any resource
- Chrome already dropped support for this (main resources only) almost 2 years ago [3].
- Firefox 37 still supports this based on local testing.

Again, I am only proposing dropping support for main resources. For e.g., having an <IMG> element in a page whose src attribute points to a Motion JPEG would still work as intended.

 Chris Dumez - Apple Inc. - Cupertino, CA

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Sam Weinig | 16 Apr 18:16 2015

Picking a text autosizing implementation


WebKit currently has two text autosizing implementations, each behind its own ENABLE macro, the
IOS_TEXT_AUTOSIZING implementation used on iOS and the TEXT_AUTOSIZING implementation.  I would like
to bring that number down to one, and compile it everywhere so we can test it on all platforms (we would still
probably want to disable it at runtime for most platforms).

Is anyone using the TEXT_AUTOSIZING implementation?  If so, would you be against switching to the
IOS_TEXT_AUTOSIZING implementation?

- Sam
Benjamin Poulain | 8 Apr 06:09 2015

Filling the features.json files

Hi WebKit,

The two features.json files are in the tree (WebCore/features.json and 
JavaScriptCore/features.json). The style checker now checks the basic 
structure of the files.

I have added some basic things in there to show the basic structure. I 
would like help setting up those lists.

If you have worked on a feature in the last 12 months, and you want to 
give it the visibility it deserves, please add it to features.json.

An other type of feature that would be useful for those files are 
features that are not as popular as they should (image-set, srcset, 
sticky-positioning, etc).

The only mandatory fields are "name" and "status".

Committers can edit those files without reviews. Other contributors can 
make patches and ping me for review.

Any question? Email me or poke me on IRC.

Brent Fulgham | 1 Apr 21:42 2015

Please be careful with webkitpy changes!

Hi Everyone,

We lost Windows EWS coverage for the past 36 hours due to a very benign-appearing change to some webkitpy
code. I haven’t yet figured out why this particular set of changes caused the Windows bots to start
failing, but it has to do with various differences between the Cygwin Python 2.7.8 build and the versions
used on our other EWS bots.

This does not seem like something developers SHOULD have to worry about, but it’s an unfortunately
reality that they really do need to.

To make matters worse, the patch that introduced the problem passed EWS. This is because the EWS bots only
really begin using changes to webkitpy when they restart processing (about once every 10-13 build iterations).

To help combat this problem, I’d like to request that when making changes to webkitpy, please keep an eye
on the various EWS bots to make sure they continue processing. If they do start failing, please roll the
patch back out and we can work together to resolve the issue.

I apologize for how manual and inconvenient this needs to be (at least for now), but keeping the EWS up and
running is critical to the smooth function of this project.

If you have any questions, please don’t hesitate to e-mail me or look for me on IRC.


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Bobby Mozumder | 27 Mar 08:49 2015

Single-page apps without Javascript W3C proposal interest?


I submitted a proposal to W3C & WHATWG to enhance HTML to support single-page apps without using Javascript:

And here’s a document on Github that’s clearer than that email:

This proposal somehow went viral:

and lots more, in different languages around the world. If you search “html6” on Twitter, you’ll see. There are hundreds or thousands of shares, upvotes, comments, etc.  

So it looks like a lot of people want something like this to happen.  I believe it represents web developers’ dissatisfaction in having to use these Javascript frameworks to do something basic that should have been a part of the HTML spec, that is, dynamic loading of content.  I put this proposal out there as a result of my own frustrations with these frameworks being constantly redesigned.

I’m checking if there’s any interest from the Webkit team on this?  I’m trying to plan the next steps and probably wouldn’t proceed without at least some sort of interest or guidance from the browser vendors.  (maybe this is technically impossible, etc..) Next steps would probably include working on a full spec, and possibly implementation.  I have built WebKit nightly before, but haven’t modified any of its code, and I suspect something like this would be way beyond me time-wise to fully implement myself, but if there’s interest, I could possibly figure out some options.

Anyways do let me know of any interest.

Bobby Mozumder
FutureClaw Magazine

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Benjamin Poulain | 23 Mar 06:10 2015

Request for feedback: Status page for WebKit

Hi ,

For those who were not at that session at the contributor meeting: some
web developers have asked for a better way to follow what is being done
in WebKit without having to follow every WebKit engineers on Twitter.

On our end, having more visibility on what is enabled in Nightly could
help getting more feedback and bug reports.

Google maintains a status page for the features enabled in chrome
( and it seems to be useful. We
could try doing something similar for WebKit.

Since Webkit's engineering is distributed with all the ports and various
prototypes, the idea would be to let every contributor maintain the
status page. We would have JSON files in the tree describing features
and their states, and would pull that information from the
repository to publish that in a nicer way.

My current plan is to have 2 files, named "features.json", with the
information about our features. The files would be in
Source/JavaScriptCore/features.json and Source/WebCore/features.json.

From the feedback at the contributor meeting, I drafted the following
format for the files:
I am still not sure how to best format the list of releases where a
feature has shipped for the first time. In the draft, I used a list of
strings with a custom format.

Please have a look. Send me your feedback. If everyone still think it is
a good idea in a week, I'll start working toward putting something like
that in the tree.

ChangSeok Oh | 20 Mar 05:38 2015

Modern image formats for WebKit

Hi WebKittens.

I just saw apng support landed on webkit main stream. [1] (even it works 
for gtk port only now)
So I suddenly wonder if webkit community is getting interested in 
bringing other modern image formats like webp or jpeg-xr into webkit.
If so, I can lend my hands for it.

For webp support, as you know, we can reuse blink's codebase. [2]
For jpeg-xr supprot, I have a rough sketch for it [3] (it might be 
outdated or not fit tot of webkit though, bringing it to webkit is just 
a piece of cake. ;))

My intention is not to argue which format is better, just to ask 
community's thoughts, preferences  or like that.




Sasi San | 19 Mar 17:35 2015

Safari browser on Mac OSX complains "AudioContext.createMediaStreamSource" is undefined !


I am trying to get the live audio input from microphone using AudioContext. Safari browser complains that the "createMediaStreamSource" is undefined. here is my sample of JavaScript code. It's not able to create Audio source node. So I am not able to get the audio sample from microphone in the OnAudioProcess event handler.

        var micGain = audioContext.createGain();
            micAudioProcessor = audioContext.createJavaScriptNode(bufferSize, 1, 1);
            console.log('createJavaScriptNode Done');
        } else {
            micAudioProcessor = audioContext.createScriptProcessor(bufferSize, 1, 1);
           console.log('createScriptProcessor Done');
        // Create an AudioNode from the stream.
        if(typeof(audioContext.createMediaStreamSource) === 'function') {
            micInput = audioContext.createMediaStreamSource(inAudioStream);
        else {
            console.log('method createMediaStreamSource unavailable');

Please let me know why Safari is complaining on this API "createMediaStreamSource ". Is there any other way I can get the live audio sample from microphone on Safari browser???


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