Remove items that has never been supported

[saschanaz]

A checklist to help your pull request get merged faster:

• Summarize your changes
• Data: link to resources that verify support information (such as browser's docs, changelogs, source control, bug trackers, and tests)
• Data: if you tested something, describe how you tested with details like browser and version
• Review the results of the linter and fix problems reported (If you need help, please ask in a comment!)
• Link to related issues or pull requests, if any: Add linter for support blocks filled only with false #6809

@vinyldarkscratch Could these be checked via mdn-bcd-collector results? I found at least one item that actually has a support (AuthenticatorAttestationResponse.prototype.getTransports) and I'm sure there are several more.

[foolip]

@saschanaz this is a great PR and much needed cruft cleanup, and cross checking against collector results to make sure we're not deleting entries that actually have been implemented is a great idea. It's a pretty big PR to review/land at once though, could it be split into smaller bits? Did you use a script to produce it, so that it could be recreated on master at any time?

@ddbeck thoughts on this, given that you marked it not ready? What are the checks you'd like to see, other than careful manual review of each removal?

[foolip]

As a compat overview, here are the entries removed by this PR:

api.AuthenticatorAttestationResponse.getTransports
api.BluetoothAdvertisingData
api.BluetoothDevice.adData
api.BluetoothDevice.connectGATT
api.BluetoothDevice.deviceClass
api.BluetoothDevice.gattServer
api.BluetoothDevice.paired
api.BluetoothDevice.productID
api.BluetoothDevice.productVersion
api.BluetoothDevice.unwatchAdvertisements
api.BluetoothDevice.uuids
api.BluetoothDevice.vendorID
api.BluetoothDevice.vendorIDSource
api.BluetoothDevice.watchAdvertisements
api.BluetoothDevice.watchingAdvertisements
api.BluetoothRemoteGATTService.getCharacteristics
api.BluetoothRemoteGATTService.getIncludedService
api.BluetoothRemoteGATTService.isPrimary
api.BudgetService.getBudget
api.BudgetService.getCost
api.BudgetState
api.CSS.ic
api.CSS.lh
api.CSS.rlh
api.CSS.vb
api.CSS.vi
api.CanvasRenderingContext2D.addHitRegion.other_hit_region_options
api.CanvasRenderingContext2D.currentTransform.DOMMatrix_return_value
api.ConstrainULong
api.DOMConfiguration
api.DOMImplementationList
api.Document.dragexit_event
api.Document.mozSyntheticDocument
api.DocumentFragment.methods
api.DocumentOrShadowRoot.nodeFromPoint
api.DocumentOrShadowRoot.nodesFromPoint
api.HTMLButtonElement.menu
api.HTMLIFrameElement.setNfcFocus
api.HTMLIsIndexElement
api.HTMLMenuItemElement.command
api.HTMLTableElement.sortable
api.HTMLTableElement.stopSorting
api.IDBVersionChangeRequest.setVersion
api.NDEFMessage
api.NDEFReader
api.NDEFReadingEvent
api.NDEFRecord
api.NDEFWriter
api.PaymentAddress.regionCode
api.PerformanceFrameTiming
api.RTCIceTransport.gatheringstatechange_event
api.RTCIceTransport.getLocalCandidates
api.RTCIceTransport.getLocalParameters
api.RTCIceTransport.ongatheringstatechange
api.RTCIceTransport.onselectedcandidatepairchange
api.RTCIceTransport.onstatechange
api.RTCIceTransport.selectedcandidatepairchange_event
api.RTCIceTransport.statechange_event
api.RTCRemoteOutboundRtpStreamStats.reportsSent
api.RTCStatsReport
api.Range.compareNode
api.ReadableByteStreamController
api.ReadableStreamBYOBReader
api.ReadableStreamBYOBRequest
api.SVGMeshElement
api.ULongRange
api.Window.clipboardchange_event
api.Window.getAttention
api.Window.getAttentionWithCycleCount
api.Window.mozAnimationStartTime
api.Window.vrdisplayblur_event
api.XRPermissionDescriptor
api.XRPermissionStatus
css.at-rules.media.prefers-reduced-transparency
css.at-rules.media.scan
css.at-rules.media.scripting
css.at-rules.media.update
css.at-rules.page.bleed
css.at-rules.page.marks
css.at-rules.page.page-margin-boxes
css.at-rules.page.size
css.at-rules.viewport.viewport-fit
css.properties.azimuth
css.properties.break-after.multicol_context.always
css.properties.break-after.paged_context.recto
css.properties.break-after.region_context
css.properties.break-before.multicol_context.always
css.properties.break-before.paged_context.recto
css.properties.break-before.region_context
css.properties.break-inside.region_context
css.properties.column-fill.balance-all
css.properties.column-width.intrinsic_sizes
css.properties.font-variant.greek_accented_characters
css.properties.font-variant.uppercase_eszett
css.properties.initial-letter-align
css.properties.margin-trim
css.properties.mask-origin.fill-box
css.properties.mask-origin.stroke-box
css.properties.mask-origin.view-box
css.properties.offset-position
css.properties.ruby-position.inter-character
css.properties.text-align.justify-all
css.properties.text-align.string
css.properties.text-indent.each-line
css.properties.text-indent.hanging
css.properties.text-overflow.fade_function
css.properties.text-overflow.fade_value
css.selectors.blank
css.selectors.column
css.selectors.empty.matches_whitespace
css.selectors.first-letter.dutch_ij_digraph
css.selectors.grammar-error
css.selectors.has
css.selectors.spelling-error
css.types.attr.fallback
css.types.attr.type-or-unit
css.types.frequency-percentage
css.types.frequency
css.types.image.image
css.types.length-percentage.cap
css.types.length-percentage.ic
css.types.length-percentage.lh
css.types.length-percentage.rlh
css.types.length-percentage.vb
css.types.length-percentage.vi
css.types.length.cap
css.types.length.ic
css.types.length.lh
css.types.length.rlh
css.types.length.vb
css.types.length.vi
html.elements.command
html.elements.dir
html.elements.iframe.allowpaymentrequest
html.elements.isindex
html.elements.link.sizes
html.elements.listing
html.elements.menu.button_menus
html.elements.menu.type.type_toolbar
html.elements.multicol
html.elements.nextid
html.elements.textarea.autocapitalize
http.headers.Cache-Control.stale-if-error
http.headers.csp.Content-Security-Policy.navigate-to
http.headers.csp.Content-Security-Policy.prefetch-src
http.headers.Cookie2
http.headers.Feature-Policy.battery
http.headers.Feature-Policy.layout-animations
http.headers.Feature-Policy.picture-in-picture
http.headers.Feature-Policy.vibrate
http.headers.Feature-Policy.wake-lock
http.headers.Set-Cookie2
javascript.builtins.AsyncIterator.AsyncIterator
javascript.builtins.AsyncIterator.asIndexedPairs
javascript.builtins.AsyncIterator.drop
javascript.builtins.AsyncIterator.every
javascript.builtins.AsyncIterator.filter
javascript.builtins.AsyncIterator.find
javascript.builtins.AsyncIterator.flatMap
javascript.builtins.AsyncIterator.forEach
javascript.builtins.AsyncIterator.from
javascript.builtins.AsyncIterator.map
javascript.builtins.AsyncIterator.reduce
javascript.builtins.AsyncIterator.some
javascript.builtins.AsyncIterator.take
javascript.builtins.AsyncIterator.toArray
javascript.builtins.AsyncIterator.@@toStringTag
javascript.builtins.Iterator.Iterator
javascript.builtins.Iterator.asIndexedPairs
javascript.builtins.Iterator.drop
javascript.builtins.Iterator.every
javascript.builtins.Iterator.filter
javascript.builtins.Iterator.find
javascript.builtins.Iterator.flatMap
javascript.builtins.Iterator.forEach
javascript.builtins.Iterator.from
javascript.builtins.Iterator.map
javascript.builtins.Iterator.reduce
javascript.builtins.Iterator.some
javascript.builtins.Iterator.take
javascript.builtins.Iterator.toArray
javascript.builtins.Iterator.@@toStringTag
javascript.operators.pipeline
mathml.elements.math.overflow
mathml.elements.mglyph
mathml.elements.mlabeledtr
mathml.elements.mo.form
mathml.elements.mo.largeop
mathml.elements.mspace.linebreak
mathml.elements.mstyle.decimalpoint
mathml.elements.mstyle.infixbreakstyle
mathml.elements.mtable.alignmentscope
mathml.elements.mtable.columnwidth
mathml.elements.mtable.equalcolumns
mathml.elements.mtable.equalrows
mathml.elements.mtable.groupalign
mathml.elements.mtable.minlabelspacing
mathml.elements.mtable.side
mathml.elements.mtd.groupalign
mathml.elements.mtr.groupalign
svg.elements.textPath.method
webextensions.manifest.content_security_policy.isolated_world
webextensions.manifest.content_security_policy.sandbox
webextensions.manifest.manifest_version.v3
webextensions.match_patterns.scheme.ftps

[saschanaz]

Did you use a script to produce it, so that it could be recreated on master at any time?

Yes, this is from a customized version of #6809 where things are autodeleted. I'll try splitting this into smaller pieces.

[ddbeck]

Sorry, I apologize for forgetting to say why I marked it as not ready. I was going to suggest that we put it into draft status, like a few other PRs, and use it as a burndown for removing these topic-by-topic. For all-false features, I'm just not confident we can mass delete them. I think we need to do a little bit of work to make sure that there really was no implementation.

Alternatively, if we want to qualify each of these features within a big PR like this, I'm thinking we ought to hold back on this until the @mdn migration is done and then treat this as a semver minor version event.

[ddbeck]

Oh, also, there's a bit of work to do on MDN: if there exist actual pages for any of these, we should archive them. That's another thing I wanted to check before merging any of this.

[foolip]

I think review will inevitably turn up some issues that will take some back and forth, so splitting into a few groups would be great. I'd be happy to review smaller PRs and do some source code archeology for Blink, Gecko and WebKit to ensure no implementation has existed.

[saschanaz]

Thanks for the feedback. First things first, converting this to draft:

[saschanaz]

I doubt anyone is willing to add anything for deprecated WebVR, what do you think?

[foolip]

I tried to remove this entry but got stuck cleaning up MDN. It's referenced in examples that I didn't know how to rewrite.

[github-actions]

This pull request has merge conflicts that must be resolved before it can be merged.

[github-actions]

This pull request has merge conflicts that must be resolved before it can be merged.

[XSpielinbox]

As a compat overview, here are the entries removed by this PR:

http.headers.csp.Content-Security-Policy.navigate-to
http.headers.csp.Content-Security-Policy.prefetch-src
http.headers.Cookie2 http.headers.Feature-Policy.battery
http.headers.Feature-Policy.layout-animations
http.headers.Feature-Policy.picture-in-picture
http.headers.Feature-Policy.vibrate
http.headers.Feature-Policy.wake-lock

1. I cannot find any data at the moment for the navigate-to, layout-animations or vibrate directives.
2. prefetch-src, battery, picture-in-picture and screen-wake-lock directives seem to be supported at least by some browsers (though as Permissions-Policy). I would therefore not remove them, but rather Firefox should implement support for them too.

[github-actions]

This pull request has merge conflicts that must be resolved before it can be merged.