Absolutely-- fantastic of you to put in the effort to contribute! Enjoy your time off.
-Michal On Fri, Aug 8, 2025 at 1:43 PM Ane Diaz De Tuesta <aned...@gmail.com> wrote: > Hello, > Thanks for your code review and your feedback! > > I am currently on PTO until the last week of August, and I'll address your > comments once I'm back. > Many of the issues in my patch stem from my lack of familiarity with the > codebase, the libraries and the language, I really appreciate your guidance > and the opportunity to learn so much. > > I'll follow up with you in a few weeks :-) > > Best regards, > Ane > > On Fri 8 Aug 2025 at 19:21, Michal Mocny <mmo...@chromium.org> wrote: > >> (Sorry, was OOO last week) >> >> I think the CL is ready for landing (~few more small review comments and >> potential test updates). >> >> The feature flag right now is marked for Origin Trial, but I don't think >> OT is a good fit for this change. Instead we can set the feature as >> experimental, publicize the proposed change, clarify the spec (if needed), >> and then start a finch rollout process while watching for surprise >> feedback. I can help walk through that process once this lands! >> >> -Michal >> >> On Mon, Aug 4, 2025 at 7:56 AM Ane Diaz De Tuesta <aned...@gmail.com> >> wrote: >> >>> Thanks a lot for the clarifications! >>> >>> Sounds good, I’ll wait for Michal’s input here, and if he’s unavailable, >>> I’ll look for another code OWNER to approve the CL. By the way, in that >>> case, what’s the recommended way to assign someone else as a reviewer? >>> >>> I’m also aligned with the idea of being transparent and publicly >>> surfacing the change. Just to double-check: you’re suggesting the need (or >>> not) for an I2S really depends on whether the metrics team considers it to >>> be a compat-affecting change that warrants mention in the changelog, right? >>> That makes sense to me. >>> >>> I like the proposal of enabling the flag by default starting with a >>> specific Chrome version while keeping it as a kill-switch, just in case. >>> For what it’s worth, my team will be impacted by this change in production >>> — we currently use the layout-shift attribution data (previous + current >>> rects) together with the DPR of the screen where the CLS was recorded to >>> transform those rects into CSS pixels and overlay them on the DOM. Having a >>> way to control when the new behavior kicks in will indeed be extremely >>> helpful for us to roll out our internal changes safely. >>> >>> Thanks again for your guidance and quick responses!☀️ >>> >>> Best regards, >>> Ane :-) >>> >>> >>> On Fri 1 Aug 2025 at 18:00, Rick Byers <rby...@chromium.org> wrote: >>> >>>> In terms of the process, yes we do just land CLs behind flags (off by >>>> default, potentially turned on by the >>>> enable-experimental-web-platform-features flag). No approval is needed here >>>> for that, just from code OWNERS reviewing the CL (probably Michal in this >>>> case, but could be others too if he's busy - should be low risk as long as >>>> the flag isn't on by default). >>>> >>>> In fact I think there's an argument that you don't need an I2S at all >>>> for this as a bug fix. But the compat risk is non-trivial enough that >>>> perhaps biasing in favor of the transparency and public discussion seems is >>>> a good idea. Michal, I don't think you've historically done an I2S for >>>> other metrics semantics tweaks in the changelog >>>> <https://chromium.googlesource.com/chromium/src/+/main/docs/speed/metrics_changelog/README.md>, >>>> right? Is this case any different and so worth doing an I2S for you think? >>>> I'm happy to defer to the metrics team judgement on this as the chance of >>>> any user-visible breaking change is IMHO near zero (close to that of any >>>> other blink bugfix). >>>> >>>> In terms of 'progressively enabling the flag', it's really a judgement >>>> call on how best to do that per feature. In this case I think I'd >>>> personally bias towards just deciding whether we think it's safe to turn on >>>> and then just enabling it 100% for a certain Chromium release. That way >>>> developers can at least compare the values to the Chrome version number if >>>> needed to determine the precise semantics. But we'd leave the flag there as >>>> a 'kill switch' we could flip if needed in the event of any serious >>>> breakage (and thereby end up breaking the correlation between version >>>> number and semantics unfortunately). Since this really does feel like a bug >>>> fix that shouldn't impact user-visible functionality, I think any process >>>> involving A/B testing is overkill (and also risks causing more confusion >>>> with developers than benefit). >>>> >>>> Thanks, have a great vacation! >>>> Rick >>>> >>>> >>>> >>>> On Fri, Aug 1, 2025 at 2:43 AM Ane Diaz De Tuesta <aned...@gmail.com> >>>> wrote: >>>> >>>>> Thanks, I completely agree, the more we can highlight interoperability >>>>> and cross-browser compatibility, the better, especially as we move toward >>>>> the *Intent to Ship* stage. >>>>> >>>>> My plan is to go step by step: first land the fix, then progressively >>>>> enable the flag, assuming that’s aligned with how we usually handle this >>>>> in >>>>> the Blink Intent process (this is my first time going through it, so I >>>>> really appreciate the guidance). >>>>> >>>>> Regarding compatibility bugs for Mozilla and WebKit, I can take a look >>>>> at filing those after I return from vacation (I’ll be off for the next 3 >>>>> weeks starting today). I’m not entirely sure how to approach that part, so >>>>> any help on that front would be appreciated. >>>>> >>>>> >>>>> Excited to hear your thoughts, Michal Mocny. >>>>> >>>>> /Ane >>>>> >>>>> Le jeudi 31 juillet 2025 à 13:33:16 UTC+2, Daniel Bratell a écrit : >>>>> >>>>>> I agree that it seems like a good idea, and the only concern would be >>>>>> whether it will break things. It sounds like Michal Mocny has been on top >>>>>> of things, but what were his findings? >>>>>> >>>>>> Once it comes to the shipping decision, the more you can say about >>>>>> interoperability and compatibility, the better. >>>>>> >>>>>> For compatibility between browsers, are there bug issues in the >>>>>> Mozilla and WebKit databases already? If not, it would be great if you >>>>>> could file some so that they end up making the same fix. >>>>>> >>>>>> /Daniel >>>>>> On 2025-07-31 08:17, Ane Diaz De Tuesta wrote: >>>>>> >>>>>> Hello, >>>>>> >>>>>> It’s been about 10 days since I shared the Intent to Prototype >>>>>> proposal, and from what I gather, it has been generally well received. >>>>>> >>>>>> As I’m not entirely familiar with the process, I’d like to suggest >>>>>> the following next steps—unless there are any objections: >>>>>> >>>>>> - >>>>>> >>>>>> Merge the CL >>>>>> - >>>>>> >>>>>> Update the feature status to *“Prepare to ship”* on ChromeStatus >>>>>> - >>>>>> >>>>>> Begin drafting the *Intent to Ship* email >>>>>> >>>>>> Please let me know if you agree with this approach, or if there’s >>>>>> anything else I should address before moving forward. >>>>>> >>>>>> Thanks! >>>>>> Le mercredi 23 juillet 2025 à 14:03:28 UTC+2, Michal Mocny a écrit : >>>>>> >>>>>>> I do suspect this was more of an oversight than a specific >>>>>>> decision, and feedback from developers seems to align with Ane Diaz: >>>>>>> most >>>>>>> are having to work around this. >>>>>>> >>>>>>> However, there are clients out there who now depend on this and we >>>>>>> are reaching out to see if it's less of a total headache to fix in >>>>>>> place or >>>>>>> provide some pathway for compat. Because this is mostly used for >>>>>>> logging / >>>>>>> tooling and not for real time user experience, so far the feedback has >>>>>>> been >>>>>>> mostly that this would be fine to break and easy to fix -- but there >>>>>>> are a >>>>>>> few other consumers we want to get feedback from. >>>>>>> >>>>>>> On Tue, Jul 22, 2025 at 5:45 PM Rick Byers <rby...@chromium.org> >>>>>>> wrote: >>>>>>> >>>>>>>> Sounds like a valuable improvement, thank you! >>>>>>>> >>>>>>>> I see you're talking with @mmocny on the CL >>>>>>>> <https://chromium-review.googlesource.com/c/chromium/src/+/6624567>, >>>>>>>> that's great. I wonder if this was just an oversight in our initial >>>>>>>> design? Seems like a bug to me. Think we can just switch it (and put >>>>>>>> the >>>>>>>> change on the changelog >>>>>>>> <https://chromium.googlesource.com/chromium/src/+/refs/heads/main/docs/speed/metrics_changelog/cls.md>) >>>>>>>> without causing compat issues? Or might we need to give devs a way to >>>>>>>> opt-in to the new semantics? mmocny@ is the expert here though, >>>>>>>> so I'm happy with whatever he wants to do. >>>>>>>> >>>>>>>> Cheers, >>>>>>>> Rick >>>>>>>> >>>>>>>> On Tue, Jul 22, 2025 at 5:00 PM Ane Diaz De Tuesta < >>>>>>>> ane...@gmail.com> wrote: >>>>>>>> >>>>>>>>> Hi all, >>>>>>>>> I'd like to announce an Intent to Prototype for: >>>>>>>>> >>>>>>>>> >>>>>>>>> - *Feature name:* Layout Instability Attribution in CSS Pixels >>>>>>>>> >>>>>>>>> >>>>>>>>> - *Contact:* anediaz@gmail >>>>>>>>> >>>>>>>>> >>>>>>>>> - *Explainer:* >>>>>>>>> >>>>>>>>> https://github.com/anediaz/layout-shift-attribution-in-css-pixels/blob/main/Explainer.md >>>>>>>>> >>>>>>>>> >>>>>>>>> - *Summary:* The Layout Instability API currently reports >>>>>>>>> attribution rectangles (`prevRect` and `currentRect`) in device >>>>>>>>> pixels, >>>>>>>>> which vary based on resolution and `devicePixelRatio`. This change >>>>>>>>> proposes >>>>>>>>> reporting them in CSS pixels for consistency with other layout and >>>>>>>>> performance APIs. >>>>>>>>> >>>>>>>>> >>>>>>>>> - *Motivation:* This will align attribution with other Web >>>>>>>>> APIs, such as `getBoundingClientRect()` and make layout shift data >>>>>>>>> easier >>>>>>>>> to visualize, debug, and combine across devices and tools. >>>>>>>>> >>>>>>>>> >>>>>>>>> - *Initial public proposal:* >>>>>>>>> https://issues.chromium.org/issues/399058544 >>>>>>>>> >>>>>>>>> >>>>>>>>> - *TAG review:* Not yet requested >>>>>>>>> >>>>>>>>> >>>>>>>>> - *Risks:* None known. This change only affects how >>>>>>>>> attribution data is reported, and is gated behind a runtime flag. >>>>>>>>> >>>>>>>>> >>>>>>>>> - *Interoperability:* >>>>>>>>> - Mozilla: No signal >>>>>>>>> - WebKit: No signal >>>>>>>>> >>>>>>>>> >>>>>>>>> - *Estimated milestones:* N/A (this is a prototype only) >>>>>>>>> >>>>>>>>> >>>>>>>>> - *Footprint:* This will be implemented behind a runtime flag. >>>>>>>>> >>>>>>>>> >>>>>>>>> - *Link to entry on Chrome Platform Status: * >>>>>>>>> https://chromestatus.com/feature/5155103518228480 >>>>>>>>> >>>>>>>>> >>>>>>>>> This Intent is to begin prototyping the feature and gather >>>>>>>>> feedback. >>>>>>>>> >>>>>>>>> Thank you for your help and time. >>>>>>>>> Cheers, >>>>>>>>> Ane Diaz de Tuesta >>>>>>>>> -- >>>>>>>>> You received this message because you are subscribed to the Google >>>>>>>>> Groups "blink-dev" group. >>>>>>>>> To unsubscribe from this group and stop receiving emails from it, >>>>>>>>> send an email to blink-dev+...@chromium.org. >>>>>>>>> To view this discussion visit >>>>>>>>> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CACBGQem%2BV6_UiLktmqwDCSXC3RJaMpmNm%3DSxv%2BH6%3DY4yCk5Msg%40mail.gmail.com >>>>>>>>> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CACBGQem%2BV6_UiLktmqwDCSXC3RJaMpmNm%3DSxv%2BH6%3DY4yCk5Msg%40mail.gmail.com?utm_medium=email&utm_source=footer> >>>>>>>>> . >>>>>>>>> >>>>>>>> -- >>>>>> You received this message because you are subscribed to the Google >>>>>> Groups "blink-dev" group. >>>>>> To unsubscribe from this group and stop receiving emails from it, >>>>>> send an email to blink-dev+...@chromium.org. >>>>>> >>>>>> To view this discussion visit >>>>>> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/15ac55eb-46bc-44d4-b50b-517d21fb27een%40chromium.org >>>>>> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/15ac55eb-46bc-44d4-b50b-517d21fb27een%40chromium.org?utm_medium=email&utm_source=footer> >>>>>> . >>>>>> >>>>>> -- You received this message because you are subscribed to the Google Groups "blink-dev" group. 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