Cool! I will spot check the tagged features a little later and if everything looks good create a corresponding edit-context YAML on web-features.

And if @captainbrosset wants to comment on creating a new edit-context group (since I saw mdn/mdn#493) that'd be nice too, but probably not a blocker.

Thanks @ddbeck! I called the group edit-context here but happy to change to text-edit if that's a better name.

Thanks @ddbeck! I called the group edit-context here but happy to change to text-edit if that's a better name.

No that was just me misreading 🤦. I've edited my earlier comment to make it more obvious what the heck I was talking about.

OK, reviewing only the tagging part here: I've now compared the spec to tagged features. I'm happy with this list. I've opened a companion feature PR on web-features: web-platform-dx/web-features#496.

Again, it'd be nice to get someone who knows anything at all about this API to check to see if I've missed anything (or if there's a likely reason to hold this back—e.g., it might not actually land in 121). But I'd be OK without it too.

And if @captainbrosset wants to comment on creating a new edit-context group (since I saw mdn/mdn#493) that'd be nice too, but probably not a blocker.

Creating a new edit-context group sounds perfect!

@Elchi3 I went through all the Chrome 121 beta entries with a fine toothcomb and compiled the following lists to represent items that the collector picked up, versus ones it didn't. This time I opted for a simplified format that was quicker to compile and possibly a bit easier to go through. Does this work for you?

Features listed in Chrome 121 beta release

Found by the collector

• api.CSSImportRule.supportsText: I'm not really sure where this one fits in
• Feature detection for supported clipboard formats: https://chromestatus.com/feature/5176417696612352
  • api.ClipboardItem.supports_static
• EditContext API: https://chromestatus.com/feature/5041440373604352
  • api.CharacterBoundsUpdateEvent
  • api.CharacterBoundsUpdateEvent.CharacterBoundsUpdateEvent
  • api.CharacterBoundsUpdateEvent.rangeEnd
  • api.CharacterBoundsUpdateEvent.rangeStart
  • api.EditContext
  • api.EditContext.EditContext
  • api.EditContext.attachedElements
  • api.EditContext.characterBounds
  • api.EditContext.characterBoundsRangeStart
  • api.EditContext.characterboundsupdate_event
  • api.EditContext.compositionend_event
  • api.EditContext.compositionstart_event
  • api.EditContext.selectionEnd
  • api.EditContext.selectionStart
  • api.EditContext.text
  • api.EditContext.textformatupdate_event
  • api.EditContext.textupdate_event
  • api.EditContext.updateCharacterBounds
  • api.EditContext.updateControlBounds
  • api.EditContext.updateSelection
  • api.EditContext.updateSelectionBounds
  • api.EditContext.updateText
  • api.HTMLElement.editContext
  • api.TextFormat
  • api.TextFormat.TextFormat
  • api.TextFormat.rangeEnd
  • api.TextFormat.rangeStart
  • api.TextFormat.underlineStyle
  • api.TextFormat.underlineThickness
  • api.TextFormatUpdateEvent
  • api.TextFormatUpdateEvent.TextFormatUpdateEvent
  • api.TextFormatUpdateEvent.getTextFormats
  • api.TextUpdateEvent
  • api.TextUpdateEvent.TextUpdateEvent
  • api.TextUpdateEvent.selectionEnd
  • api.TextUpdateEvent.selectionStart
  • api.TextUpdateEvent.text
  • api.TextUpdateEvent.updateRangeEnd
  • api.TextUpdateEvent.updateRangeStart
• HTMLSelectElement showPicker(): https://chromestatus.com/feature/5111537299881984
  • api.HTMLSelectElement.showPicker
• CSS Scrollbars: scrollbar-color, scrollbar-width: https://chromestatus.com/feature/5665308343795712
  • css.properties.scrollbar-color
  • css.properties.scrollbar-width
• CSS spelling and grammar features: https://chromestatus.com/feature/4811776539492352
  • css.selectors.grammar-error
  • css.selectors.spelling-error
• Array.fromAsync: https://chromestatus.com/feature/5069575759069184
  • javascript.builtins.Array.fromAsync

Not found by the collector

• Discard Input Events To Recently Moved Cross-Origin Iframes: https://chromestatus.com/feature/5079376387637248 (more of a browser behavior thing)
• Attribution Reporting Feature Bundle: Reduced Aggregate Delays, Event-Level Report Epsilon Field, Reserved Keys: https://chromestatus.com/feature/5181611197071360 (hidden behind enrollment?)
• CSS font-palette property animation: https://chromestatus.com/feature/5177171439517696 (behavior change rather than a new property)
• CSS Highlight Inheritance: https://chromestatus.com/feature/5090853643354112 (behavior change rather than a new property)
• CSS supports() condition for @import: https://chromestatus.com/feature/5899007704694784 (addition to @import syntax)
• Document picture-in-picture: require user gesture for resize APIs: https://chromestatus.com/feature/5398995019235328 (Window returned by DocumentPictureInPicture.requestWindow() can now use resizeBy() and resizeTo() with user gesture)
• Improved CSS masking for SVG: https://chromestatus.com/feature/5138520058626048 (CSS masking stuff)
• MediaCapabilities: Query HDR support with decodingInfo(): https://chromestatus.com/feature/6640863931269120 (HdrMetadataType option added to MediaCapabilities.encodingInfo dictionary parameter)
• No-Vary-Search Hint for Prefetch Speculation Rules: https://chromestatus.com/feature/4887338302308352 (new field for speculation rule JSON structure)
• No-Vary-Search support in navigation prefetch cache: https://chromestatus.com/feature/5071247189213184 (new HTTP header)
• Private Aggregation API: aggregation coordinator selection: https://chromestatus.com/feature/5140711678935040 (hidden behind enrollment?)
• Protected Audience Ad slot size in real-time bidding signals fetch and update more interest group fields: https://chromestatus.com/feature/5090856430469120
• Remote Playback API: https://chromestatus.com/feature/5778318691401728 (surprised this one wasn't found)
• Ruby-specific display values: https://chromestatus.com/feature/6416726833233920 (new display property values, default display values for <ruby> and <rt> elements)
• Speculation rules: delivery via Speculation-Rules header: https://chromestatus.com/feature/5069400512659456 (new HTTP header)
• Speculation rules: document-sourced rules: https://chromestatus.com/feature/5112150536749056 (new field for speculation rule JSON structure; predicate?)
• Speculation rules: eagerness field: https://chromestatus.com/feature/5091678266851328 (new field for speculation rule JSON structure)
• Expose SpeechSynthesis and SpeechSynthesisVoice interface objects: https://chromestatus.com/feature/4818803819020288 (not even sure if there is anything to do here)
• Storage Buckets API: https://chromestatus.com/feature/5739224579964928 (surprised this one wasn't found)
• URLPattern: Inherit left, wildcard right: https://chromestatus.com/feature/6076647526891520 (changes to inheritance behavior of URLPattern)
• URLPattern: RegExp v flag instead of u: https://chromestatus.com/feature/5122651463090176 (internal behavior change to enable unicode sets in URLPatterns)
• WebGPU default entry points to shader modules: https://chromestatus.com/feature/5102870756327424 (GPUProgrammableStage)
• WebGPU timestamp queries: https://chromestatus.com/feature/5136606877188096 (GPUComputePassTimestampWrites)
• X25519Kyber768 key encapsulation for TLS: https://chromestatus.com/feature/5257822742249472 (not really sure how we'd document this)
  Multiple Readers and Writers in File System Access API: https://chromestatus.com/feature/5172892632875008 (new locking modes for FileSystemSyncAccessHandle and FileSystemWritableFileStream)
• Set IndexedDB transaction durability to relaxed by default: https://chromestatus.com/feature/5084460341264384 (IDBDatabase.transaction durability option now defaults to relaxed)

Thanks once again Chris for your detailed analysis. It will help us to detect more things automatically in the future. ❤️

Some comments on items not found:

• As said previously, features that are "behavior things" aren't really subject to our automatic collection. So thanks for listing them, but right now we can't do anything about them automatically.
• Same for features that are new parameters and other sub features: not always subject to automatic collection right now.
• Enrollment. We have to see how to support enrollment in the collector and how to have a note on BCD features that are only available when enrolled. This is a to-do for BCD and the collector. Right now it is very tricky to tell if they are supported.
• HTTP features aren't automatically collected currently. I don't know how we could feature detect these. Something to think about. I think we should add the new HTTP header in a separate PR manually.

Two things that seem like we should have detected them with our current infrastructure:

Remote Playback API: https://chromestatus.com/feature/5778318691401728 (surprised this one wasn't found).

Yes, I am surprised too. We have #21486 to investigate the situation. Seems like the API was exposed for a long time already and so we feature detected it when it shipped to Android already.

Storage Buckets API: https://chromestatus.com/feature/5739224579964928 (surprised this one wasn't found).

Yes, strange. I wonder if this slipped to 122? See https://wpt.fyi/results/storage/buckets?label=master&product=chrome-121.0.6167.8%20beta&product=chrome%5Bexperimental%5D&aligned where the WPT fail for 121 and pass for 122. Maybe Chromestatus is wrong?

@chrisdavidmills I'm not planning to add more to this PR. If what this PR changes, looks good to you, I'd appreciate an approval and merge. :) I left some comments for the rest, but that should probably be sorted in other PRs.

@chrisdavidmills I'm not planning to add more to this PR. If what this PR changes, looks good to you, I'd appreciate an approval and merge. :) I left some comments for the rest, but that should probably be sorted in other PRs.

@Elchi3. Sure thing; merging!