Not yet stable

For a given set of browsers, what APIs are not yet in all of them.

Example Comparisons
Browsers
Features

Summary

A count of the number of APIs are in Browser X but not in Browser Y.
Not in ChromeNot in Firefox
In Chrome 136
In Firefox 11

Unstable APIs

Below is a list of features that are not in all of Chrome and Firefox

Raw Data

Quick Links:

HTML Data

API First Browser Date Days in Limbo Notes
html.elements.a.attributionsrc 📋Chrome5/14/2024810
html.elements.a.coords 📋Chrome12/11/20086443
Firefox: You can no longer nest an <a> element inside a <map> element to create a hotspot region - coords and shape attribute support removed.Firefox for Android: You can no longer nest an <a> element inside a <map> element to create a hotspot region - coords and shape attribute support removed.
html.elements.a.href.href_sms Firefox4/24/20125213
html.elements.a.hreftranslate Chrome4/7/20202308
html.elements.a.referrerpolicy.no-referrer-when-downgrade Chrome5/25/20163721
html.elements.a.referrerpolicy.origin-when-cross-origin Chrome5/25/20163721
html.elements.a.referrerpolicy.unsafe-url Chrome5/25/20163721
html.elements.a.shape 📋Chrome12/11/20086443
Firefox: You can no longer nest an <a> element inside a <map> element to create a hotspot region - coords and shape attribute support removed.Firefox for Android: You can no longer nest an <a> element inside a <map> element to create a hotspot region - coords and shape attribute support removed.
html.elements.a.target.unfencedTop Chrome7/18/20231111
html.elements.area.referrerpolicy.no-referrer-when-downgrade Chrome5/25/20163721
html.elements.area.referrerpolicy.origin-when-cross-origin Chrome5/25/20163721
html.elements.area.referrerpolicy.unsafe-url Chrome5/25/20163721
html.elements.audio.controlslist 📋Chrome4/19/20173392
html.elements.audio.disableremoteplayback 📋Chrome1/23/2024922
html.elements.canvas.moz-opaque Firefox6/30/20096242
html.elements.col.char 📋Chrome12/11/20086443
html.elements.col.charoff 📋Chrome12/11/20086443
html.elements.colgroup.char 📋Chrome12/11/20086443
html.elements.colgroup.charoff 📋Chrome12/11/20086443
html.elements.fencedframe 📋Chrome7/18/20231111
html.elements.fencedframe.allow 📋Chrome7/18/20231111
html.elements.fencedframe.height 📋Chrome7/18/20231111
html.elements.fencedframe.width 📋Chrome7/18/20231111
html.elements.form.autocomplete.new-password Firefox5/21/20192630
html.elements.form.autocomplete.webauthn 📋Chrome11/29/20221342
html.elements.iframe.allow.accelerometer 📋Chrome4/17/20183029
html.elements.iframe.allow.ambient-light-sensor 📋Chrome4/17/20183029
html.elements.iframe.allow.attribution-reporting 📋Chrome9/12/20231055
html.elements.iframe.allow.bluetooth 📋Chrome8/2/20221461
html.elements.iframe.allow.browsing-topics Chrome7/18/20231111
html.elements.iframe.allow.compute-pressure 📋Chrome5/14/2024810
html.elements.iframe.allow.cross-origin-isolated 📋Chrome11/17/20202084
html.elements.iframe.allow.gamepad 📋Firefox8/10/20211818
Firefox: The default allowlist is * instead of self (as required by the specification).Firefox for Android: The default allowlist is * instead of self (as required by the specification).
html.elements.iframe.allow.gyroscope 📋Chrome4/17/20183029
html.elements.iframe.allow.hid 📋Chrome3/2/20211979
html.elements.iframe.allow.identity-credentials-get 📋Chrome2/7/20231272
html.elements.iframe.allow.idle-detection 📋Chrome9/21/20211776
html.elements.iframe.allow.local-fonts 📋Chrome6/21/20221503
html.elements.iframe.allow.magnetometer 📋Chrome4/17/20183029
html.elements.iframe.allow.otp-credentials 📋Chrome8/31/20211797
html.elements.iframe.allow.picture-in-picture 📋Chrome12/4/20182798
html.elements.iframe.allow.publickey-credentials-create 📋Firefox2/20/2024894
html.elements.iframe.allow.serial 📋Chrome3/2/20211979
html.elements.iframe.allow.speaker-selection 📋Firefox8/1/20231097
Firefox for Android: Not available due to a limitation in Android (see bug 1473346).
html.elements.iframe.allow.storage-access 📋Chrome5/2/20231188
html.elements.iframe.allow.usb 📋Chrome7/25/20173295
html.elements.iframe.allow.wildcards Chrome11/29/20221342
html.elements.iframe.allow.window-management 📋Chrome3/29/20221587
html.elements.iframe.allow.xr-spatial-tracking 📋Chrome12/10/20192427
html.elements.iframe.allowpaymentrequest Chrome7/25/20173295
html.elements.iframe.browsingtopics Chrome7/18/20231111
html.elements.iframe.credentialless 📋Chrome2/7/20231272
html.elements.iframe.csp 📋Chrome9/5/20173253
html.elements.iframe.referrerpolicy.no-referrer-when-downgrade Chrome5/25/20163721
html.elements.iframe.referrerpolicy.origin-when-cross-origin Chrome5/25/20163721
html.elements.iframe.referrerpolicy.unsafe-url Chrome5/25/20163721
html.elements.iframe.sandbox.allow-top-navigation-to-custom-protocols 📋Firefox5/31/20221524
html.elements.img.attributionsrc 📋Chrome5/14/2024810
html.elements.img.referrerpolicy.no-referrer-when-downgrade Chrome5/25/20163721
html.elements.img.referrerpolicy.origin-when-cross-origin Chrome5/25/20163721
html.elements.img.referrerpolicy.unsafe-url Chrome5/25/20163721
html.elements.img.sizes.auto 📋Chrome6/11/2024782
html.elements.input.type_month 📋Chrome6/26/20125150
Safari: The input type is recognized, but there is no month-specific control. See bug 200416.
html.elements.input.type_password.insecure_login_handling Firefox3/7/20173435
html.elements.input.type_week 📋Chrome6/26/20125150
html.elements.link.blocking 📋Chrome9/2/20221430
html.elements.link.referrerpolicy.no-referrer-when-downgrade Chrome5/25/20163721
html.elements.link.referrerpolicy.origin-when-cross-origin Chrome5/25/20163721
html.elements.link.referrerpolicy.unsafe-url Chrome5/25/20163721
html.elements.link.rel.alternate_stylesheet 📋Firefox6/17/20086620
html.elements.link.rel.expect 📋Chrome4/16/2024838
html.elements.link.rel.manifest 📋Chrome11/18/20144275
html.elements.link.rel.preload.as-track Chrome4/13/20163763
html.elements.link.rel.prerender Chrome8/2/20115479
html.elements.meta.name.application-title Chrome3/4/2025516
html.elements.meta.name.theme-color 📋Chrome3/12/20192700
Chrome: Chrome uses the color only on installed progressive web apps.Chrome: Chrome reports support, but does not actually use the color anywhere.Chrome Android: Chrome for Android does not use the color on devices with native dark mode enabled unless it's an installed progressive web app or a trusted web activity.Edge: Edge uses the color only on installed progressive web apps.Quest Browser: Chrome for Android does not use the color on devices with native dark mode enabled unless it's an installed progressive web app or a trusted web activity.
html.elements.script.attributionsrc 📋Chrome5/14/2024810
html.elements.script.blocking 📋Chrome9/2/20221430
html.elements.script.referrerpolicy.no-referrer-when-downgrade Chrome10/16/20182847
html.elements.script.referrerpolicy.origin-when-cross-origin Chrome10/16/20182847
html.elements.script.referrerpolicy.unsafe-url Chrome10/16/20182847
html.elements.script.type.importmap.integrity 📋Chrome7/23/2024740
html.elements.script.type.importmap.multiple_import_maps 📋Chrome2/4/2025544
html.elements.script.type.speculationrules 📋Chrome1/10/20231300
Chrome: Initial support included same-origin prerendering only.Chrome Android: Initial support included same-origin prerendering only.Edge: Initial support included same-origin prerendering only.Quest Browser: Initial support included same-origin prerendering only.Opera: Initial support included same-origin prerendering only.Opera Android: Initial support included same-origin prerendering only.Samsung Internet: Initial support included same-origin prerendering only.
html.elements.script.type.speculationrules.eagerness Chrome1/23/2024922
html.elements.script.type.speculationrules.expects_no_vary_search Chrome7/23/2024740
Chrome: Supported for prefetch only.Chrome Android: Supported for prefetch only.Edge: Supported for prefetch only.Opera: Supported for prefetch only.Opera Android: Supported for prefetch only.Samsung Internet: Supported for prefetch only.
html.elements.script.type.speculationrules.prefetch Chrome2/7/20231272
html.elements.script.type.speculationrules.prerender Chrome9/2/20221430
html.elements.script.type.speculationrules.referrer_policy Chrome3/7/20231244
html.elements.script.type.speculationrules.relative_to Chrome1/23/2024922
html.elements.script.type.speculationrules.requires Chrome2/7/20231272
html.elements.script.type.speculationrules.requires.anonymous-client-ip-when-cross-origin Chrome2/7/20231272
html.elements.script.type.speculationrules.source_optional Chrome2/20/2024894
html.elements.script.type.speculationrules.urls Chrome1/10/20231300
html.elements.script.type.speculationrules.where Chrome1/23/2024922
html.elements.style.blocking 📋Chrome9/2/20221430
html.elements.tbody.char Chrome12/11/20086443
html.elements.td.char Chrome12/11/20086443
html.elements.template.shadowrootserializable 📋Chrome5/14/2024810
html.elements.textarea.autocomplete.new-password Firefox5/21/20192630
html.elements.textarea.autocomplete.webauthn 📋Chrome11/29/20221342
html.elements.textarea.wrap.hard Chrome12/13/20115346
html.elements.tfoot.char Chrome12/11/20086443
html.elements.th.char Chrome12/11/20086443
html.elements.th.rowspan.rowspan_zero Firefox8/8/20173281
html.elements.thead.char Chrome12/11/20086443
html.elements.tr.char Chrome12/11/20086443
html.elements.tr.charoff Chrome12/11/20086443
html.elements.video.controlslist 📋Chrome4/19/20173392
html.elements.video.disableremoteplayback 📋Chrome1/23/2024922
html.elements.video.playsinline 📋Chrome6/4/20192616
html.global_attributes.contenteditable.plaintext-only Chrome5/25/20163721
html.global_attributes.hidden.until-found 📋Chrome5/24/20221531
html.global_attributes.virtualkeyboardpolicy 📋Chrome9/21/20211776
html.global_attributes.writingsuggestions 📋Chrome4/16/2024838
html.manifest.background_color 📋Chrome10/13/20153946
html.manifest.description 📋Chrome1/19/20212021
Firefox for Android: The property parses, but has no effect.
html.manifest.display 📋Chrome11/18/20144275
Chrome: display and/or display_override are required for a web app to be installable.Chrome Android: display and/or display_override are required for a web app to be installable.Edge: display and/or display_override are required for a web app to be installable.Quest Browser: display and/or display_override are required for a web app to be installable.Opera: display and/or display_override are required for a web app to be installable.Opera Android: display and/or display_override are required for a web app to be installable.Samsung Internet: display and/or display_override are required for a web app to be installable.WebView Android: display and/or display_override are required for a web app to be installable.
html.manifest.display.browser 📋Chrome11/18/20144275
html.manifest.display.fullscreen 📋Chrome11/18/20144275
html.manifest.display.minimal-ui 📋Chrome11/18/20144275
html.manifest.display.standalone 📋Chrome11/18/20144275
html.manifest.display_override 📋Chrome3/2/20211979
Chrome: display_override and/or display are required for a web app to be installable.Chrome Android: display_override and/or display are required for a web app to be installable.Edge: display_override and/or display are required for a web app to be installable.Quest Browser: display_override and/or display are required for a web app to be installable.Opera: display_override and/or display are required for a web app to be installable.Opera Android: display_override and/or display are required for a web app to be installable.Samsung Internet: display_override and/or display are required for a web app to be installable.
html.manifest.display_override.tabbed 📋Chrome6/11/2024782
html.manifest.display_override.window-controls-overlay 📋Chrome9/2/20221430
html.manifest.file_handlers 📋Chrome5/24/20221531
html.manifest.icons 📋Chrome11/18/20144275
Chrome: icons is required for a web app to be installable.Chrome Android: icons is required for a web app to be installable.Edge: icons is required for a web app to be installable.Quest Browser: icons is required for a web app to be installable.Opera: icons is required for a web app to be installable.Opera Android: icons is required for a web app to be installable.Safari: Only used when no apple-touch-icon is present and either "purpose" is set to "any" or "purpose" is not specified.Safari on iOS: Only used when no apple-touch-icon is present and either "purpose" is set to "any" or "purpose" is not specified.Samsung Internet: icons is required for a web app to be installable.WebView Android: icons is required for a web app to be installable.WebView on iOS: Only used when no apple-touch-icon is present and either "purpose" is set to "any" or "purpose" is not specified.
html.manifest.id 📋Chrome11/15/20211721
Firefox: The property parses, but has no effect.
html.manifest.launch_handler 📋Chrome2/7/20231272
html.manifest.launch_handler.client_mode 📋Chrome2/7/20231272
html.manifest.name 📋Chrome11/18/20144275
Chrome: name or short_name is required for a web app to be installable.Chrome Android: name or short_name is required for a web app to be installable.Edge: name or short_name is required for a web app to be installable.Quest Browser: name or short_name is required for a web app to be installable.Opera: name or short_name is required for a web app to be installable.Opera Android: name or short_name is required for a web app to be installable.Samsung Internet: name or short_name is required for a web app to be installable.WebView Android: name or short_name is required for a web app to be installable.
html.manifest.note_taking 📋Chrome10/19/20211748
html.manifest.note_taking.new_note_url 📋Chrome10/19/20211748
html.manifest.orientation 📋Chrome11/18/20144275
html.manifest.protocol_handlers 📋Chrome11/15/20211721
html.manifest.protocol_handlers.protocol 📋Chrome11/15/20211721
html.manifest.protocol_handlers.url 📋Chrome11/15/20211721
html.manifest.scope 📋Chrome8/31/20163623
html.manifest.serviceworker Chrome10/16/20182847
html.manifest.serviceworker.scope Chrome10/16/20182847
html.manifest.serviceworker.src Chrome10/16/20182847
html.manifest.serviceworker.use_cache Chrome10/16/20182847
html.manifest.share_target 📋Chrome3/2/20211979
Firefox for Android: The property parses, but has no effect.
html.manifest.short_name 📋Chrome11/18/20144275
Chrome: short_name or name is required for a web app to be installable.Chrome Android: short_name or name is required for a web app to be installable.Edge: short_name or name is required for a web app to be installable.Quest Browser: short_name or name is required for a web app to be installable.Opera: short_name or name is required for a web app to be installable.Opera Android: short_name or name is required for a web app to be installable.Samsung Internet: short_name or name is required for a web app to be installable.WebView Android: short_name or name is required for a web app to be installable.
html.manifest.shortcuts 📋Chrome11/15/20211721
Chrome: Supported on Windows only.Edge: Supported on Windows only.Opera: Supported on Windows only.
html.manifest.start_url 📋Chrome11/18/20144275
Chrome: start_url is required for a web app to be installable.Chrome Android: start_url is required for a web app to be installable.Edge: start_url is required for a web app to be installable.Quest Browser: start_url is required for a web app to be installable.Opera: start_url is required for a web app to be installable.Opera Android: start_url is required for a web app to be installable.Samsung Internet: start_url is required for a web app to be installable.WebView Android: start_url is required for a web app to be installable.
html.manifest.theme_color 📋Chrome10/13/20153946