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 EdgeNot in Safari
In Edge 96
In Safari 8

Unstable APIs

Below is a list of features that are not in all of Edge and Safari

Raw Data

Quick Links:

HTML Data

API First Browser Date Days in Limbo Notes
html.elements.a.attributionsourceid 📋Safari4/26/20211788
html.elements.a.attributionsrc 📋Edge5/17/2024671
html.elements.a.interestfor Edge10/31/2025139
html.elements.a.referrerpolicy.no-referrer-when-downgrade Edge1/15/20202255
html.elements.a.referrerpolicy.origin-when-cross-origin Edge1/15/20202255
html.elements.a.referrerpolicy.unsafe-url Edge1/15/20202255
html.elements.a.target.unfencedTop Edge6/13/2024644
html.elements.area.attributionsrc 📋Edge5/17/2024671
html.elements.area.interestfor Edge10/31/2025139
html.elements.area.referrerpolicy.no-referrer-when-downgrade Edge1/15/20202255
html.elements.area.referrerpolicy.origin-when-cross-origin Edge1/15/20202255
html.elements.area.referrerpolicy.unsafe-url Edge1/15/20202255
html.elements.audio.controlslist 📋Edge1/15/20202255
html.elements.button.interestfor Edge10/31/2025139
html.elements.dialog.closedby 📋Edge3/6/2025378
html.elements.fencedframe 📋Edge6/13/2024644
html.elements.fencedframe.allow 📋Edge6/13/2024644
html.elements.fencedframe.height 📋Edge6/13/2024644
html.elements.fencedframe.width 📋Edge6/13/2024644
html.elements.geolocation 📋Edge1/21/202657
html.elements.geolocation.autolocate 📋Edge1/21/202657
html.elements.geolocation.watch 📋Edge1/21/202657
html.elements.h1.no_ua_styles_in_article_aside_nav_section 📋Safari12/12/202597
html.elements.iframe.allow.accelerometer 📋Edge1/15/20202255
html.elements.iframe.allow.ambient-light-sensor 📋Edge1/15/20202255
html.elements.iframe.allow.attribution-reporting 📋Edge9/15/2023916
html.elements.iframe.allow.autoplay 📋Edge1/15/20202255
html.elements.iframe.allow.bluetooth 📋Edge8/5/20221322
html.elements.iframe.allow.browsing-topics Edge7/21/2023972
html.elements.iframe.allow.compute-pressure 📋Edge5/17/2024671
html.elements.iframe.allow.cross-origin-isolated 📋Edge11/19/20201946
html.elements.iframe.allow.document-domain 📋Edge1/15/20202255
html.elements.iframe.allow.encrypted-media 📋Edge1/15/20202255
html.elements.iframe.allow.fullscreen 📋Edge1/15/20202255
html.elements.iframe.allow.geolocation 📋Edge1/15/20202255
html.elements.iframe.allow.gyroscope 📋Edge1/15/20202255
html.elements.iframe.allow.hid 📋Edge3/4/20211841
html.elements.iframe.allow.identity-credentials-get 📋Edge2/9/20231134
html.elements.iframe.allow.idle-detection 📋Edge9/24/20211637
html.elements.iframe.allow.local-fonts 📋Edge6/23/20221365
html.elements.iframe.allow.magnetometer 📋Edge1/15/20202255
html.elements.iframe.allow.midi 📋Edge1/15/20202255
html.elements.iframe.allow.otp-credentials 📋Edge9/2/20211659
html.elements.iframe.allow.payment 📋Edge1/15/20202255
html.elements.iframe.allow.picture-in-picture 📋Edge1/15/20202255
html.elements.iframe.allow.publickey-credentials-get 📋Edge7/16/20202072
html.elements.iframe.allow.serial 📋Edge3/4/20211841
html.elements.iframe.allow.storage-access 📋Edge5/5/20231049
html.elements.iframe.allow.usb 📋Edge1/15/20202255
html.elements.iframe.allow.web-share 📋Edge10/9/20201987
Firefox: Firefox recognizes the web-share permissions policy, but this has no effect in versions of Firefox that do not support the share() method.Firefox for Android: Firefox for Android recognizes the web-share permissions policy, but this has no effect in versions of Firefox for Android that do not support the share() method.
html.elements.iframe.allow.wildcards Edge12/5/20221200
html.elements.iframe.allow.window-management 📋Edge4/1/20221448
html.elements.iframe.allow.xr-spatial-tracking 📋Edge1/15/20202255
html.elements.iframe.allowpaymentrequest Edge1/15/20202255
html.elements.iframe.browsingtopics Edge6/13/2024644
html.elements.iframe.credentialless 📋Edge2/9/20231134
html.elements.iframe.csp 📋Edge1/15/20202255
html.elements.iframe.privateToken 📋Edge9/15/2023916
html.elements.iframe.referrerpolicy.no-referrer-when-downgrade Edge1/15/20202255
html.elements.iframe.referrerpolicy.origin-when-cross-origin Edge1/15/20202255
html.elements.iframe.referrerpolicy.unsafe-url Edge1/15/20202255
html.elements.iframe.sandbox.allow-orientation-lock 📋Edge1/15/20202255
html.elements.iframe.sandbox.allow-presentation 📋Edge1/15/20202255
html.elements.iframe.sandbox.allow-top-navigation-to-custom-protocols 📋Safari9/12/20221284
html.elements.img.attributionsrc 📋Edge5/17/2024671
html.elements.img.referrerpolicy.no-referrer-when-downgrade Edge1/15/20202255
html.elements.img.referrerpolicy.origin-when-cross-origin Edge1/15/20202255
html.elements.img.referrerpolicy.unsafe-url Edge1/15/20202255
html.elements.img.sizes.auto 📋Edge6/13/2024644
html.elements.input.alpha 📋Safari3/31/2025353
html.elements.input.colorspace 📋Safari3/31/2025353
html.elements.input.switch Safari3/5/2024744
html.elements.input.type_color.accepts_css_colors 📋Safari3/31/2025353
html.elements.input.type_month 📋Edge7/29/20153886
Safari: The input type is recognized, but there is no month-specific control. See bug 200416.
html.elements.input.type_range.labeled_values 📋Edge1/15/20202255
html.elements.input.type_week 📋Edge7/29/20153886
html.elements.link.referrerpolicy.no-referrer-when-downgrade Edge1/15/20202255
html.elements.link.referrerpolicy.origin-when-cross-origin Edge1/15/20202255
html.elements.link.referrerpolicy.unsafe-url Edge1/15/20202255
html.elements.link.rel.compression-dictionary 📋Edge10/17/2024518
html.elements.link.rel.expect 📋Edge4/18/2024700
html.elements.link.rel.modulepreload.as-style 📋Edge4/9/2026-21
html.elements.link.rel.prerender Edge1/15/20202255
Chrome: Does not trigger prerendering. Triggers NoState Prefetch instead. See blog post.Chrome Android: Does not trigger prerendering. Triggers NoState Prefetch instead. See blog post.Edge: Does not trigger prerendering. Triggers NoState Prefetch instead. See blog post.Quest Browser: Does not trigger prerendering. Triggers NoState Prefetch instead. See blog post.Opera: Does not trigger prerendering. Triggers NoState Prefetch instead. See blog post.Opera Android: Does not trigger prerendering. Triggers NoState Prefetch instead. See blog post.WebView Android: Does not trigger prerendering. Triggers NoState Prefetch instead. See blog post.
html.elements.meta.name.application-title Edge3/6/2025378
html.elements.script.attributionsrc 📋Edge5/17/2024671
html.elements.script.referrerpolicy.no-referrer-when-downgrade Edge1/15/20202255
html.elements.script.referrerpolicy.origin-when-cross-origin Edge1/15/20202255
html.elements.script.referrerpolicy.unsafe-url Edge1/15/20202255
html.elements.script.type.speculationrules.expects_no_vary_search 📋Edge7/25/2024602
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.WebView Android: Supported for prefetch only.
html.elements.script.type.speculationrules.prerender 📋Edge9/1/20221295
html.elements.script.type.speculationrules.requires 📋Edge2/9/20231134
html.elements.script.type.speculationrules.target_hint 📋Edge6/26/2025266
Chrome: Only "_blank" and "_self" are supported and only for prefetch.Chrome Android: Only "_blank" and "_self" are supported and only for prefetch.Edge: Only "_blank" and "_self" are supported and only for prefetch.Opera: Only "_blank" and "_self" are supported and only for prefetch.Opera Android: Only "_blank" and "_self" are supported and only for prefetch.WebView Android: Only "_blank" and "_self" are supported and only for prefetch.
html.elements.selectedcontent 📋Edge4/4/2025349
html.elements.summary.display_list_item Edge3/4/20211841
html.elements.td.rowspan.rowspan_zero Edge1/15/20202255
html.elements.textarea.autocomplete.webauthn 📋Edge12/5/20221200
html.elements.textarea.wrap.hard Edge7/29/20153886
html.elements.video.controlslist 📋Edge1/15/20202255
html.global_attributes.autocapitalize 📋Edge1/15/20202255
html.global_attributes.autocorrect 📋Safari4/26/20211788
html.global_attributes.inert.ignores_find_in_page 📋Edge4/18/2024700
html.global_attributes.is 📋Edge1/15/20202255
html.global_attributes.popover.hint 📋Edge2/6/2025406
html.global_attributes.virtualkeyboardpolicy 📋Edge9/24/20211637