I've definitely heard back from several companies (large and small) of the need for this. Erik Witt's analysis may be the only public support we've got, but there are a number of non-public teams waiting for this too.
On Mon, 2 Jun 2025 at 19:25, Alex Russell <slightly...@chromium.org> wrote: > Thanks for this. I'm a little concerned that this is a workaround for an > implementation-based restriction in chromium, and that the goal is to > remove that restriction through rearchitecture at some point in the near > future. Do we have a timeline for that? > > It would also be helpful to understand the need more clearly. The data > from Erik Witt was helpful in the sense that it showed the feature works as > intended, but I wasn't able to understand the overall impact, as there > wasn't a way to judge those auxiliary context opens as a fraction of > traffic. Was there more conclusive evidence of the need from other partners? > > Best, > > Alex > On Wednesday, May 28, 2025 at 5:57:25 PM UTC-7 Domenic Denicola wrote: > >> On Thu, May 29, 2025 at 12:33 AM Alex Russell <slightly...@chromium.org> >> wrote: >> >>> The justification for this feature in the Explainer seems a bit thin. >>> What's the core problem that requires us to make developers repeat >>> themselves like this rather than, e.g., deriving the target information >>> from attributes on <a> elements? >>> >> >> For <a> elements and speculation rules that select them, this information >> is automatically derived. The use case here is for when URLs are listed >> explicitly, using the `"urls": [a, b, c]` syntax. Such speculations are >> most important for pages that reach the given URLs via JavaScript, or via >> redirects, or other means such that the URL is not directly inside a >> `href=""`. >> >> I agree that the example which the explainer leads with does not make >> this clear. We'll do a pass to rewrite and clarify the main use case. >> >> >>> >>> On Wednesday, May 28, 2025 at 8:26:10 AM UTC-7 Chris Harrelson wrote: >>> >>>> LGTM2 >>>> >>>> On Tue, May 27, 2025 at 7:52 AM Mike Taylor <miketa...@chromium.org> >>>> wrote: >>>> >>>>> Thanks, LGTM1. >>>>> On 5/23/25 2:15 AM, Domenic Denicola wrote: >>>>> >>>>> >>>>> >>>>> On Wednesday, May 21, 2025 at 10:31:06 PM UTC+9 Mike Taylor wrote: >>>>> >>>>> On 5/20/25 6:06 AM, Chromestatus wrote: >>>>> >>>>> Contact emails robert...@chromium.org >>>>> >>>>> Explainer https://github.com/WICG/nav-speculation/blob/main/ >>>>> triggers.md#window-name-targeting-hints >>>>> >>>>> Specification https://wicg.github.io/nav- >>>>> speculation/speculation-rules.html >>>>> >>>>> Summary >>>>> >>>>> This extends speculation rules syntax to allow developers to specify >>>>> the target_hint field. This field provides a hint to indicate a target >>>>> navigable where a prerendered page will eventually be activated. For >>>>> example, when _blank is specified as a hint, a prerendered page can be >>>>> activated for a navigable opened by window.open(). The field has no effect >>>>> on prefetching. The specification allows this field to accept any strings >>>>> that are valid as navigable target name or keyword as the value, but this >>>>> launch supports only one of "_self" or "_blank" strings. If the hint is >>>>> not >>>>> specified, it's treated like "_self" is specified. >>>>> >>>>> >>>>> Blink component Internals>Preload>Prerender >>>>> <https://issues.chromium.org/issues?q=customfield1222907:%22Internals%3EPreload%3EPrerender%22> >>>>> >>>>> Search tags speculationrules <http:///features#tags:speculationrules>, >>>>> prerendering <http:///features#tags:prerendering> >>>>> >>>>> TAG review https://github.com/w3ctag/design-reviews/issues/931 >>>>> >>>>> TAG review status Issues addressed >>>>> >>>>> Origin Trial Name SpeculationRulesTargetHint >>>>> >>>>> Chromium Trial Name SpeculationRulesTargetHint >>>>> >>>>> Origin Trial documentation link https://github.com/WICG/nav- >>>>> speculation/blob/main/triggers.md#window-name-targeting-hints >>>>> >>>>> WebFeature UseCounter name kSpeculationRulesTargetHintBlank >>>>> >>>>> Risks >>>>> >>>>> >>>>> Interoperability and Compatibility >>>>> >>>>> This feature is a small addition to the existing speculation rules >>>>> feature. Speculation rules itself is a progressive enhancement, so the >>>>> interoperability risks are low. Additionally, the compatibility risks for >>>>> this feature are low: if we removed it in the future, it would cause some >>>>> prerenders to start failing, but prerendering is never guaranteed to work >>>>> and is hard to depend on. >>>>> >>>>> >>>>> *Gecko*: Neutral (https://github.com/mozilla/ >>>>> standards-positions/issues/620) Mozilla was notified about this >>>>> addition to the speculation rules syntax on the overall speculation rules >>>>> standards positions thread, and gave an overall neutral response to the >>>>> feature. >>>>> >>>>> *WebKit*: No signal (https://github.com/WebKit/ >>>>> standards-positions/issues/54) >>>>> >>>>> *Web developers*: No signals >>>>> >>>>> *Other signals*: SpeedKit/Baqend https://github.com/WICG/nav- >>>>> speculation/issues/374 We also know of a Google site which has >>>>> experimented with this feature and successfully used it to enable >>>>> prerendering which was previously not possible >>>>> >>>>> WebView application risks >>>>> >>>>> Does this intent deprecate or change behavior of existing APIs, such >>>>> that it has potentially high risk for Android WebView-based applications? >>>>> >>>>> None >>>>> >>>>> >>>>> Debuggability >>>>> >>>>> DevTools supports speculation rules: https://developer.chrome.com/ >>>>> blog/debugging-speculation-rules/ >>>>> >>>>> >>>>> Will this feature be supported on all six Blink platforms (Windows, >>>>> Mac, Linux, ChromeOS, Android, and Android WebView)? No >>>>> >>>>> Android WebView doesn't support speculation rules prerender yet. >>>>> >>>>> >>>>> Is this feature fully tested by web-platform-tests >>>>> <https://chromium.googlesource.com/chromium/src/+/main/docs/testing/web_platform_tests.md> >>>>> ? Yes >>>>> >>>>> https://wpt.fyi/results/speculation-rules/prerender >>>>> >>>>> I see that many (most?) of the target_hint tests are failing in the >>>>> latest Canary. Is that expected? >>>>> >>>>> >>>>> We've been struggling with this for some time. You'll notice that this >>>>> is a general problem with all prerender tests, not specific to the new >>>>> target_hint feature. >>>>> >>>>> Ultimately, we believe that something about how these tests are >>>>> written makes them not play well with the automation used on wpt.fyi. Note >>>>> that Edge passes many of the tests we fail, and sometimes we pass tests >>>>> that Edge fails, likely due to different test infrastructure details on >>>>> Windows (Edge) vs. Linux (Chrome). >>>>> >>>>> This is somewhat understandable, as prerender involves hidden >>>>> navigables which can confuse the test runner, as well as lots of >>>>> cross-document messages. We have a few projects under way to clean up the >>>>> testing infrastructure here and hopefully make it more reliable, but >>>>> they've been slow-burning. They would certainly shoot up in urgency if we >>>>> saw active interest from other implementers in prerender. (We're seeing >>>>> some for prefetch right now, so prerender might be soon!) >>>>> >>>>> >>>>> >>>>> >>>>> Flag name on about://flags >>>>> enable-speculation-rules-prerendering-target-hint >>>>> >>>>> >>>>> Finch feature name Prerender2InNewTab >>>>> >>>>> Rollout plan Will ship enabled for all users >>>>> >>>>> Requires code in //chrome? False >>>>> >>>>> Tracking bug https://issues.chromium.org/issues/40234240 >>>>> >>>>> Availability expectation Feature is available on Web Platform in >>>>> M138. >>>>> >>>>> Sample links >>>>> https://prerender2-specrules.glitch.me >>>>> >>>>> Estimated milestones Shipping on desktop 138 Origin trial desktop >>>>> first 135 Origin trial desktop last 138 Shipping on Android 138 Origin >>>>> trial Android first 135 Origin trial Android last 138 >>>>> >>>>> Anticipated spec changes >>>>> >>>>> Open questions about a feature may be a source of future web compat or >>>>> interop issues. Please list open issues (e.g. links to known github issues >>>>> in the project for the feature specification) whose resolution may >>>>> introduce web compat/interop risk (e.g., changing to naming or structure >>>>> of >>>>> the API in a non-backward-compatible way). >>>>> No spec changes are planned. >>>>> >>>>> Link to entry on the Chrome Platform Status https://chromestatus.com/ >>>>> feature/5162540351094784?gate=5144913335549952 >>>>> >>>>> Links to previous Intent discussions Intent to Experiment: >>>>> https://groups.google.com/a/chromium.org/d/msgid/blink- >>>>> dev/67c935cc.2b0a0220.325104.02b6.GAE%40google.com >>>>> >>>>> >>>>> This intent message was generated by Chrome Platform Status >>>>> <https://chromestatus.com>. >>>>> >>>>> -- >>>>> 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+unsubscr...@chromium.org. >>>>> To view this discussion visit https://groups.google.com/a/ >>>>> chromium.org/d/msgid/blink-dev/682c5413.2b0a0220.146035. >>>>> 0187.GAE%40google.com >>>>> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/682c5413.2b0a0220.146035.0187.GAE%40google.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+unsubscr...@chromium.org. >>>>> >>>> To view this discussion visit >>>>> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/8833a3d5-5e77-405f-ad9b-dc80a9f8b6e0%40chromium.org >>>>> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/8833a3d5-5e77-405f-ad9b-dc80a9f8b6e0%40chromium.org?utm_medium=email&utm_source=footer> >>>>> . >>>>> >>>> -- > You received this message because you are subscribed to a topic in the > Google Groups "blink-dev" group. > To unsubscribe from this topic, visit > https://groups.google.com/a/chromium.org/d/topic/blink-dev/am_noPAIH5k/unsubscribe > . > To unsubscribe from this group and all its topics, send an email to > blink-dev+unsubscr...@chromium.org. > To view this discussion visit > https://groups.google.com/a/chromium.org/d/msgid/blink-dev/b0fafb6c-764a-48c4-8f3f-cd9dcd5a72fen%40chromium.org > <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/b0fafb6c-764a-48c4-8f3f-cd9dcd5a72fen%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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