Just to be clear, when you say "spelling and grammar hints" are you referring to the marker drawn under the word or some other hint (suggestions, though they require specific interaction already, I believe)? Maybe use "marker" instead of "hint".
Assuming you mean markers, for context it's worth saying that CSS allows styling of the spelling and grammar markers, and by applying things like large text shadows to misspelled words the rendering time can be significantly impacted. You can enhance the impact by adding additional custom highlights to the word. With that in mind I fully support this intent. Stephen. On Thu, Oct 9, 2025 at 11:45 AM Ari Chivukula <[email protected]> wrote: > Contact emails > > [email protected], [email protected], [email protected], > [email protected] > Explainer/Specification > > https://explainers-by-googlers.github.io/user-dictionary-leaks/ > > Summary > > This experiment would change when spelling and grammar hints are applied > to text fields to reduce the of websites ability to extract information > about the user’s dictionary, specifically: > > - > > Hints would not be applied to a text field that has not had user > interaction (an autofocus > > <https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes/autofocus> > is insufficient, there must be a click or key press of some kind relative > to that field). > - > > Hints would only be applied once per user interaction (the text cannot > be changed programmatically and have hints applied without a click or key > press of some kind relative to that field). > > > Blink component > > Blink>Editing>Spellcheck > <https://issues.chromium.org/issues?q=customfield0:%22Blink%3EEditing%3ESpellcheck%22> > > TAG review > > https://github.com/w3ctag/design-reviews/issues/1148 > > > Motivation > > The user’s dictionary may contain sensitive information, for example some > operating systems import the contents of the user’s address book to assist > with the spelling of names/addresses. Although direct indicators of the > ::spelling-error and ::grammar-error cannot be extracted, it’s possible > to extract indirect information from browsers without rate limits on the > application of these hints. In Chrome and Firefox, it’s possible to have an > autofocused > <https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes/autofocus> > text area cycle programmatically through a series of misspelled words, and > for the site to monitor indicators of rendering performance to notice when > hints are applied. This allows sites (or their third-party embeds) to > detect which words are or aren’t in the user’s dictionary, which could leak > sensitive information stored there (for example, their contacts' names). > Safari already has rate limits in place which only check for and apply > hints once per user interaction with the text field (e.g., a key input or > click). > > Risks > > Interoperability and Compatibility > > Safari is already in full compliance with these changes, while Firefox and > Chrome are only in partial compliance with the first one (they do count > autofocused fields, but don’t apply new hints to fields that aren’t in > active focus). > > Gecko: https://github.com/mozilla/standards-positions/issues/1294 > > WebKit: https://github.com/WebKit/standards-positions/issues/546 > > Debuggability > > This isn’t exposed to DevTools. > > Measurement > > UMA will be added to the SpellChecker > <https://source.chromium.org/chromium/chromium/src/+/main:third_party/blink/renderer/core/editing/spellcheck/spell_checker.h> > class that notes when hints are registered to the document so that browsers > in and out of the experiment can be compared. > > 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? > > No, this isn’t observable outside browsertests. > > Flag name on about://flags > > N/A > > Finch feature name > > RestrictSpellingAndGrammarHighlights > > Rollout plan > > 1% experiment on stable to see if this causes any drop in key metrics. > > Requires code in //chrome? > > No > > Tracking bug > > https://crbug.com/415712674 > > Estimated milestones > > 143 > > Link to entry on the Chrome Platform Status > > https://chromestatus.com/feature/5080415048171520 > > -- > 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/CAGpy5DJnHAOx7Khuqgu-xLgmu3R4UYeqfrkqVasuQx4A0JK_vg%40mail.gmail.com > <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAGpy5DJnHAOx7Khuqgu-xLgmu3R4UYeqfrkqVasuQx4A0JK_vg%40mail.gmail.com?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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