LGTM1 On Tue, Nov 4, 2025 at 8:55 AM Mike Taylor <[email protected]> wrote:
> Hello, > > Could you please request reviews for the Privacy, Security, Enterprise, > Debuggability, and Testing bits in your chromestatus entry? > On 10/31/25 6:03 a.m., Chromestatus wrote: > > *Contact emails* > [email protected], [email protected] > > *Specification* > https://w3c.github.io/mathml-core/#layout-of-operators > > *Summary* > Support for character-level and glyph-level mirroring when rendering > MathML operators in right-to-left mode. When using RTL mode some operators > can be mirrored by changing them to another code point (e.g. a right > parentheses becomes a left parentheses). This is character-level mirroring, > with equivalences defined by Unicode's `Bidi_Mirrored` property. There are > operators that have no appropriate mirroring character. Glyph-level > mirroring applies in this case, with the `rtlm` font feature, where another > glyph can replace it in a mirrored context. Some existing implementations > mirror the original glyph directly, but this may change the meaning for > asymmetrical characters, such as the clockwise contour integral. > > *Blink component* > Blink>MathML > <https://issues.chromium.org/issues?q=customfield1222907:%22Blink%3EMathML%22> > > *Web Feature ID* > mathml <https://webstatus.dev/features/mathml> > > *Motivation* > Arabic mathematical notations require rendering math operator in > right-to-left mode, where operators need to be correctly mirrored. > Sometimes, a simple horizontal flip is not enough. In the case of > asymmetrical glyphs like a clockwise contour integral doing so would change > the meaning of the symbol. That's why both character-level mirroring and > glyph-level mirroring is needed to produce a correct mathematical > expression in RTL mode. The following explainer shows the different cases > to consider when mirroring stretchy characters, as well as the proposed > MathML Core spec amendments to support this use case: > https://people.igalia.com/fwang/mathml-operator-mirroring-explainer.html > > *Initial public proposal* > *No information provided* > > *TAG review* > *No information provided* > > *TAG review status* > Not applicable > > *Risks* > > > *Interoperability and Compatibility* > *No information provided* > > *Gecko*: Shipped/Shipping ( > https://bugzilla.mozilla.org/show_bug.cgi?id=945183) Shipped under the > `mathml.rtl_operator_mirroring.enabled` flag. Will be enabled by default > once Firefox 146 releases. > > *WebKit*: In development Already has character-level mirroring. rtlm > support is being worked on for the harfbuzz ports. > > *Web developers*: No signals > > *Other signals*: > > *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? > *No information provided* > > > *Debuggability* > *No information provided* > > *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 > New tests: - Character-level mirroring: checks that when switching text > direction the codepoints of the characters change to the corresponding > BidiMirrored equivalent (e.g. right to left parentheses) - Glyph-level > mirroring: checks that the rtlm font feature is supported and that a > specific glyph is used for certain characters when switching text direction. > > *Flag name on about://flags* > *No information provided* > > *Finch feature name* > MathMLOperatorRTLMirroring > > *Rollout plan* > Will ship enabled for all users > > *Requires code in //chrome?* > False > > *Tracking bug* > https://issues.chromium.org/issues/40120782 > > *Availability expectation* > Feature already available on Firefox and partially available on WebKit, > with plans to make it fully available within the next months. > > *Adoption expectation* > Feature is used for the case of rendering right to left math. > > *Adoption plan* > It will ship enabled by default so users can start benefiting from it. > > *Non-OSS dependencies* > > Does the feature depend on any code or APIs outside the Chromium open > source repository and its open-source dependencies to function? > No. > > *Estimated milestones* > Shipping on desktop 144 > DevTrial on desktop 140 > Shipping on Android 144 > DevTrial on Android 140 > Shipping on WebView 144 > Shipping on iOS 144 > > *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. > > *Link to entry on the Chrome Platform Status* > https://chromestatus.com/feature/6317308531965952?gate=4798753084801024 > > *Links to previous Intent discussions* > Intent to Prototype: > https://groups.google.com/a/chromium.org/d/msgid/blink-dev/686d2758.170a0220.a35ba.00d7.GAE%40google.com > Ready for Trial: > https://groups.google.com/a/chromium.org/g/blink-dev/c/IpmWeJSPR0g > > > 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 [email protected]. > To view this discussion visit > https://groups.google.com/a/chromium.org/d/msgid/blink-dev/69048958.710a0220.23debc.007c.GAE%40google.com > <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/69048958.710a0220.23debc.007c.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 [email protected]. > To view this discussion visit > https://groups.google.com/a/chromium.org/d/msgid/blink-dev/37255b52-5d54-43f6-80c0-262f45ba9cf3%40chromium.org > <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/37255b52-5d54-43f6-80c0-262f45ba9cf3%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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