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Explainer https://open-ui.org/components/select Specification https://github.com/whatwg/html/issues/9799 (see sub-PRs linked there) Design docs https://open-ui.org/components/select Summary Customizable <select> allows developers to take complete control of the rendering of <select>, including the ability to fully customize both the in-page “button” element as well as the popup picker, with arbitrary content within options. Developers can opt in to this new behavior with a simple CSS declaration that uses a new `base-select` value for the `appearance` property. This new capability has been in development for a very long time, starting in late 2019 <https://www.youtube.com/watch?v=ZFvPLrKZywA> in earnest (with the original explainer <https://github.com/MicrosoftEdge/MSEdgeExplainers/blob/main/ControlUICustomization/explainer.md> from June 2020). Due to that early work, two other platform APIs were identified as prerequisites for customizable-<select>: the popover API and anchor positioning. Now, with both of those APIs landed in standards and browsers, the customizable-<select> is unblocked. Once the customizable-<select> feature began to get discussed in standards (at OpenUI in 2020 <https://github.com/openui/open-ui/issues?q=is%3Aissue%20label%3Aselect%20sort%3Acreated-asc>, and in WHATWG <https://github.com/whatwg/html/issues/9799> and CSSWG in mid-2023), it rapidly evolved. Not only did the names of the elements change (<selectmenu>, <selectlist>, then <select>, etc.) but the shape of the API changed considerably. It evolved from a very shadow-DOM centric API using things like the slot attribute to a more HTML-like API using new elements such as the <selectedcontent> element. The WHATWG/CSSWG/OpenUI joint task force worked through the question of how to opt-in to the new behavior, selecting among a new element, an HTML attribute, a CSS property, or something else, and arrived at a consensus of using the CSS appearance property. Many discussions were had (e.g. in OpenUI <https://github.com/openui/open-ui/issues/540> and WHATWG <https://github.com/whatwg/html/issues/10317>) about the content model and the allowed set of controls, to ensure the new control is accessible and rational, while still providing a very flexible, powerful API to developers. Overall, the standards process shaped this API into something that follows platform conventions, has natural naming and methods to achieve goals, and builds naturally upon recently added features such as popover, anchor positioning, interactivity:inert, and many others. In addition, the construction of the customizable-<select> API has been a huge catalyst to find other missing platform features and quirks, such as corner cases <https://github.com/whatwg/html/pull/10770> in the popover API. Throughout this process, we’ve worked hard to reach out to the developer community, to ensure all common use cases are supported, there aren’t lingering compat issues, and the new customizable-<select> control is as accessible as possible. In some cases, e.g. the necessary changes to the HTML parser to allow arbitrary content, there is still some compat risk. We are working hard to increase our confidence that we can ship those changes via (separate <https://chromestatus.com/feature/5145948356083712>) Finch testing and rollout. However, at this point, we are confident that we have reached a stable API shape with a low level of risk. Blink component Blink>Forms>Select Search tags select <https://chromestatus.com/features#tags:select>, custom select <https://chromestatus.com/features#tags:custom%20select>, controls <https://chromestatus.com/features#tags:controls>, form controls <https://chromestatus.com/features#tags:form%20controls>, custom controls <https://chromestatus.com/features#tags:custom%20controls>, custom form controls <https://chromestatus.com/features#tags:custom%20form%20controls> TAG review https://github.com/w3ctag/design-reviews/issues/1007 TAG review status Issues resolved Risks Interoperability and Compatibility Interop risk is low because we have been designing this feature closely with Apple and Mozilla during the standardization process over the last 15 months. Changing the HTML parser for <select> elements is a prerequisite for this change and has some compat risks, which had a separate intent here: https://groups.google.com/a/chromium.org/g/blink-dev/c/5_9-Qkvlj2M/m/Q96A126vAAAJ Gecko: No signal https://github.com/mozilla/standards-positions/issues/1060 WebKit: No signal https://github.com/WebKit/standards-positions/issues/386 Web developers: Very strongly positive https://2024.stateofhtml.com/en-US/features/#reading_list Other signals: Ergonomics None in particular. Activation Clear documentation will be required to help developers understand the opt in and how to style and replace various parts of the new select element. We already have some documentation here but will create another blog post for launching the feature: - https://developer.chrome.com/blog/rfc-customizable-select - https://una.im/select-updates/ Security The picker for customizable select does not extend outside of the web contents like an appearance:auto select does, so there should not be any new capabilities exposed which would have security considerations. 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 The customizable select should already be fairly debuggable via existing DevTools features. The new select does add a few new pseudo-elements, which have been added to DevTools. Will this feature be supported on all six Blink platforms (Windows, Mac, Linux, ChromeOS, Android, and Android WebView)? Yes 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/html/semantics/forms/the-select-element/customizable-select Flag name on about://flags None Finch feature name CustomizableSelect Non-finch justification None Requires code in //chrome? False Tracking bug https://crbug.com/40146374 Estimated milestones 134 Anticipated spec changes Customizable select is currently in stage 2 <https://whatwg.org/stages#stage2> in WHATWG. We have had spec PRs open for review since August of last year <https://github.com/whatwg/html/pull/10548>, and we have been repeatedly asking for reviews and feedback at WHATNOT meetings. However, we have not received stage 3 <https://whatwg.org/stages#stage3> approval yet, which means that the other implementers have not yet signed off on the final design. These are the only remaining open issues that have been raised, and we don’t anticipate any significant changes based on the resolutions of these: - Should alt text be included in select.value? <https://github.com/whatwg/html/issues/10317> - How should we write about user interactions and events in the spec? <https://github.com/whatwg/html/issues/10762> Link to entry on the Chrome Platform Status https://chromestatus.com/feature/5737365999976448 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/CAK6btw%2BX5UTWoDCGNUCpEUHYh%2BhgddTgOerGHugFnBGbQnb-Rg%40mail.gmail.com.
