Time to Stable

For a given set of browsers, what APIs are in all of them and how many days it take for the API to land in the first browser to the last.

Example Comparisons
Browsers
Features

Summary

A count of the number of APIs that landed in A first and B last.
Last in EdgeLast in Safari
First in Edge 54
First in Safari 123

Average time for an API to become available across Edge and Safari

177 APIs took an average of 2195.72 days to become available to use.

API breakdown:

Average time to landing by year of first landing

If a feature landed in the earliest browser in 20XX it took Y days on average to become available in the last browser (when considering Edge and Safari). TTA (time to available).
HTTP APIsHTTP TTA
2003 584503.36
2008 43096.75
2009 102242.00
2010 21878.00
2012 51099.00
2013 211317.67
2015 1783.00
2016 8877.13
2017 12438.00
2018 7708.43
2019 5153.60
2020 281024.18
2021 1493.00
2022 6389.00
2023 4750.25
2024 4551.50
2025 1225.00

The Tortoise and the Hare

There is a natural tension on the web with respect to browser engines. Every engine has their own set of priorities which define the level of investment that they choose to make and on which areas they choose to make it.

A developer naturally wants their experiences to be available to the widest audience possible and these differing priorities create an unevenness on the platform (a lumpiness) making it harder for developers to build experiences that work everywhere.

This section highlights where browsers are pushing and pulling on the platform.

Sprinters

This table is designed to show which browsers are pushing on the platform the most.

Adding features to quickly is not always desired because developers are unlikely to adopt those features in their sites or apps.

For a given year, if a feature landed in Browser X first, how many days it take on average to be available in Edge and Safari. TTA (time to available).
Year HTTPHTTP TTA
2003
  Safari 584503.36
2008
  Safari 43096.75
2009
  Safari 102242.00
2010
  Safari 21878.00
2012
  Safari 51099.00
2013
  Safari 211317.67
2015
  Edge 1783.00
2016
  Safari 8877.13
2017
  Edge 8345.25
  Safari 4623.50
2018
  Safari 6616.67
  Edge 11259.00
2019
  Safari 5153.60
2020
  Edge 281024.18
2021
  Edge 1493.00
2022
  Edge 6389.00
2023
  Edge 4750.25
2024
  Edge 4551.50
2025
  Edge 1225.00

Plodders

This table is designed to show which browsers are pulling on the platform the most.

For a feature that first landed in year X, how many days did it take on average for the last browser to catch up across Edge and Safari. TTA (time to available).
Year HTTP countHTTP TTA
2003
  Edge 584503.36
2008
  Edge 43096.75
2009
  Edge 102242.00
2010
  Edge 21878.00
2012
  Edge 51099.00
2013
  Edge 211317.67
2015
  Safari 1783.00
2016
  Edge 8877.13
2017
  Safari 8345.25
  Edge 4623.50
2018
  Edge 6616.67
  Safari 11259.00
2019
  Edge 5153.60
2020
  Safari 281024.18
2021
  Safari 1493.00
2022
  Safari 6389.00
2023
  Safari 4750.25
2024
  Safari 4551.50
2025
  Safari 1225.00

Stable APIs

Below is a list of features that are in Edge and Safari

Raw Data

Quick Links:

HTTP Data

API First Browser Date Last Browser Date Days Notes
http.data-url 📋Safari3/18/2008 Edge7/29/20152689
Edge: Before Edge 79, the maximum size supported is 4GB.Internet Explorer: Since Internet Explorer 9, the maximum size supported is 4GB.Internet Explorer: In Internet Explorer 8, the maximum size supported is 32kB.
http.data-url.css_files Safari3/18/2008 Edge7/29/20152689
http.data-url.html_files Safari3/18/2008 Edge1/15/20204320
http.data-url.js_files Safari3/18/2008 Edge7/29/20152689
http.data-url.top_level_navigation_blocked Edge1/15/2020 Safari9/16/2020245
http.headers.Accept 📋Safari6/23/2003 Edge7/29/20154419
Firefox: In Firefox 66, the default Accept header value changed to */*.Firefox for Android: In Firefox for Android 66, the default Accept header value changed to */*.
http.headers.Accept-Encoding 📋Safari6/23/2003 Edge7/29/20154419
http.headers.Accept-Encoding.br 📋Edge4/5/2017 Safari9/19/2017167
Safari: Unsupported before macOS 10.13 High Sierra.
http.headers.Accept-Encoding.zstd 📋Edge3/22/2024 Safari2/11/2026691
Safari: Before macOS 26.3 Tahoe, this header value is not sent.
http.headers.Accept-Language 📋Safari6/23/2003 Edge7/29/20154419
http.headers.Accept-Ranges 📋Safari6/23/2003 Edge7/29/20154419
http.headers.Access-Control-Allow-Credentials 📋Safari6/8/2009 Edge7/29/20152242
http.headers.Access-Control-Allow-Headers 📋Safari6/8/2009 Edge7/29/20152242
http.headers.Access-Control-Allow-Headers.wildcard Safari9/19/2019 Edge1/15/2020118
http.headers.Access-Control-Allow-Methods 📋Safari6/8/2009 Edge7/29/20152242
http.headers.Access-Control-Allow-Methods.wildcard Safari9/19/2019 Edge1/15/2020118
http.headers.Access-Control-Allow-Origin 📋Safari6/8/2009 Edge7/29/20152242
http.headers.Access-Control-Expose-Headers 📋Safari6/8/2009 Edge7/29/20152242
http.headers.Access-Control-Expose-Headers.wildcard Safari9/19/2019 Edge1/15/2020118
http.headers.Access-Control-Max-Age 📋Safari6/8/2009 Edge7/29/20152242
http.headers.Access-Control-Request-Headers 📋Safari6/8/2009 Edge7/29/20152242
http.headers.Access-Control-Request-Method 📋Safari6/8/2009 Edge7/29/20152242
http.headers.Age 📋Safari6/23/2003 Edge7/29/20154419
http.headers.Alt-Svc 📋Edge1/15/2020 Safari9/18/20231342
Firefox: Only supports draft-04Firefox for Android: Only supports draft-04
http.headers.Authorization 📋Safari6/23/2003 Edge7/29/20154419
http.headers.Authorization.Basic 📋Safari6/23/2003 Edge7/29/20154419
http.headers.Authorization.Digest 📋Safari6/23/2003 Edge1/15/20206050
http.headers.Authorization.Digest.md5 Safari6/23/2003 Edge1/15/20206050
http.headers.Authorization.NTLM Safari10/22/2013 Edge1/15/20202276
http.headers.Authorization.Negotiate 📋Safari10/22/2013 Edge1/15/20202276
http.headers.Cache-Control 📋Safari6/23/2003 Edge7/29/20154419
http.headers.Cache-Control.stale-while-revalidate 📋Edge1/15/2020 Safari9/16/2020245
http.headers.Clear-Site-Data 📋Edge1/15/2020 Safari9/18/20231342
http.headers.Clear-Site-Data.cache 📋Edge1/15/2020 Safari9/18/20231342
Chrome: Setting this value may increase response duration (see bug 40233601.Chrome: Setting this value may prevent a page from fully load (see bug 41343050.Chrome Android: Setting this value may increase response duration (see bug 40233601.Chrome Android: Setting this value may prevent a page from fully load (see bug 41343050.Edge: Setting this value may increase response duration (see bug 40233601.Quest Browser: Setting this value may increase response duration (see bug 40233601.Opera: Setting this value may increase response duration (see bug 40233601.Opera: Setting this value may prevent a page from fully load (see bug 41343050.Opera Android: Setting this value may increase response duration (see bug 40233601.Opera Android: Setting this value may prevent a page from fully load (see bug 41343050.Samsung Internet: Setting this value may increase response duration (see bug 40233601.WebView Android: Setting this value may increase response duration (see bug 40233601.WebView Android: Setting this value may prevent a page from fully load (see bug 41343050.
http.headers.Clear-Site-Data.cookies 📋Edge1/15/2020 Safari9/18/20231342
http.headers.Clear-Site-Data.secure_context_required Edge1/15/2020 Safari9/18/20231342
http.headers.Clear-Site-Data.storage 📋Edge1/15/2020 Safari9/18/20231342
http.headers.Clear-Site-Data.wildcard 📋Edge9/15/2023 Safari9/18/20233
http.headers.Connection 📋Safari6/23/2003 Edge7/29/20154419
http.headers.Content-Disposition 📋Safari6/23/2003 Edge7/29/20154419
Chrome: When saving documents, the document title is used instead of the filename parameter if the disposition type is inline. See bug 352093465.Chrome Android: When saving documents, the document title is used instead of the filename parameter if the disposition type is inline. See bug 352093465.Firefox: From version 82, if an <a> element's download attribute is set (for a same-origin URL) then the inline directive is ignored. Earlier versions did not match the specification and respected the header directive over the attribute. See bug 1658877.Firefox for Android: From version 82, if an <a> element's download attribute is set (for a same-origin URL) then the inline directive is ignored. Earlier versions did not match the specification and respected the header directive over the attribute. See bug 1658877.Quest Browser: When saving documents, the document title is used instead of the filename parameter if the disposition type is inline. See bug 352093465.Opera: When saving documents, the document title is used instead of the filename parameter if the disposition type is inline. See bug 352093465.Opera Android: When saving documents, the document title is used instead of the filename parameter if the disposition type is inline. See bug 352093465.Safari: When saving documents, the document title is used instead of the filename parameter if the disposition type is inline. See bug 18384.Safari on iOS: When saving documents, the document title is used instead of the filename parameter if the disposition type is inline. See bug 18384.Samsung Internet: When saving documents, the document title is used instead of the filename parameter if the disposition type is inline. See bug 352093465.WebView Android: When saving documents, the document title is used instead of the filename parameter if the disposition type is inline. See bug 352093465.WebView on iOS: When saving documents, the document title is used instead of the filename parameter if the disposition type is inline. See bug 18384.
http.headers.Content-Encoding 📋Safari6/23/2003 Edge7/29/20154419
http.headers.Content-Encoding.br 📋Edge4/5/2017 Safari9/19/2017167
Safari: Unsupported before macOS 10.13 High Sierra.
http.headers.Content-Encoding.zstd 📋Edge3/22/2024 Safari2/11/2026691
Safari: Before macOS 26.3 Tahoe, Safari cannot decode Zstandard responses.
http.headers.Content-Language 📋Safari6/23/2003 Edge7/29/20154419
http.headers.Content-Length 📋Safari6/23/2003 Edge7/29/20154419
http.headers.Content-Length.cors_response_safelist Safari3/25/2019 Edge1/15/2020296
http.headers.Content-Location 📋Safari6/23/2003 Edge7/29/20154419
http.headers.Content-Range 📋Safari6/23/2003 Edge7/29/20154419
http.headers.Content-Security-Policy 📋Safari10/22/2013 Edge8/2/20161015
Internet Explorer: Only supporting 'sandbox' directive.
http.headers.Content-Security-Policy.base-uri 📋Safari9/20/2016 Edge1/15/20201212
http.headers.Content-Security-Policy.block-all-mixed-content Safari9/20/2016 Edge1/15/20201212
Chrome: Will be removed, see bug 40260100.Chrome Android: Will be removed, see bug 40260100.Edge: Will be removed, see bug 40260100.Quest Browser: Will be removed, see bug 40260100.Opera: Will be removed, see bug 40260100.Opera Android: Will be removed, see bug 40260100.Samsung Internet: Will be removed, see bug 40260100.WebView Android: Will be removed, see bug 40260100.
http.headers.Content-Security-Policy.child-src 📋Safari9/20/2016 Edge4/5/2017197
http.headers.Content-Security-Policy.connect-src 📋Safari10/22/2013 Edge8/2/20161015
Firefox: Before Firefox 50, ping attributes of <a> elements weren't covered by connect-src.
http.headers.Content-Security-Policy.default-src 📋Safari10/22/2013 Edge8/2/20161015
http.headers.Content-Security-Policy.font-src 📋Safari10/22/2013 Edge8/2/20161015
http.headers.Content-Security-Policy.form-action 📋Safari9/20/2016 Edge4/5/2017197
http.headers.Content-Security-Policy.form-action.blocks_redirects Safari4/12/2018 Edge1/15/2020643
http.headers.Content-Security-Policy.frame-ancestors 📋Safari9/20/2016 Edge4/5/2017197
Firefox: Before Firefox 58, frame-ancestors is ignored in Content-Security-Policy-Report-Only.Firefox for Android: Before Firefox for Android 58, frame-ancestors is ignored in Content-Security-Policy-Report-Only.
http.headers.Content-Security-Policy.frame-src 📋Safari10/22/2013 Edge8/2/20161015
http.headers.Content-Security-Policy.img-src 📋Safari10/22/2013 Edge8/2/20161015
http.headers.Content-Security-Policy.manifest-src 📋Safari9/19/2017 Edge1/15/2020848
http.headers.Content-Security-Policy.media-src 📋Safari10/22/2013 Edge8/2/20161015
http.headers.Content-Security-Policy.meta-element-support Safari10/22/2013 Edge10/2/20181806
http.headers.Content-Security-Policy.object-src 📋Safari10/22/2013 Edge8/2/20161015
http.headers.Content-Security-Policy.report-sample Edge1/15/2020 Safari3/14/2022789
http.headers.Content-Security-Policy.report-to 📋Edge1/15/2020 Safari3/27/20231167
http.headers.Content-Security-Policy.report-uri 📋Safari10/22/2013 Edge8/2/20161015
http.headers.Content-Security-Policy.require-trusted-types-for 📋Edge5/21/2020 Safari9/15/20251943
http.headers.Content-Security-Policy.sandbox 📋Safari10/22/2013 Edge8/2/20161015
http.headers.Content-Security-Policy.script-src 📋Safari10/22/2013 Edge8/2/20161015
http.headers.Content-Security-Policy.script-src.external_scripts 📋Edge1/15/2020 Safari7/20/2022917
http.headers.Content-Security-Policy.script-src.inline-speculation-rules Edge2/9/2023 Safari12/12/20251037
http.headers.Content-Security-Policy.script-src.wasm-unsafe-eval Edge1/6/2022 Safari9/12/2022249
http.headers.Content-Security-Policy.script-src-attr 📋Edge1/15/2020 Safari3/14/2022789
http.headers.Content-Security-Policy.script-src-elem 📋Edge1/15/2020 Safari3/14/2022789
http.headers.Content-Security-Policy.strict-dynamic Edge1/15/2020 Safari3/14/2022789
http.headers.Content-Security-Policy.style-src 📋Safari10/22/2013 Edge8/2/20161015
http.headers.Content-Security-Policy.style-src-attr 📋Edge1/15/2020 Safari3/14/2022789
http.headers.Content-Security-Policy.style-src-elem 📋Edge1/15/2020 Safari12/12/20252158
Safari: The style-src-elem directive was parsed, but had no effect. See bug 276931.Safari on iOS: The style-src-elem directive was parsed, but had no effect. See bug 276931.WebView on iOS: The style-src-elem directive was parsed, but had no effect. See bug 276931.
http.headers.Content-Security-Policy.trusted-types 📋Edge5/21/2020 Safari9/15/20251943
http.headers.Content-Security-Policy.unsafe-hashes Edge1/15/2020 Safari3/14/2022789
http.headers.Content-Security-Policy.upgrade-insecure-requests 📋Safari3/27/2017 Edge4/30/2018399
http.headers.Content-Security-Policy.worker-src 📋Edge1/15/2020 Safari5/16/2022852
Chrome: Chrome 59 and higher skips the deprecated child-src directive.Chrome Android: Chrome Android 59 and higher skips the deprecated child-src directive.Quest Browser: Quest Browser 5.0 and higher skips the deprecated child-src directive.Opera: Opera 46 and higher skips the deprecated child-src directive.Opera Android: Opera Android 43 and higher skips the deprecated child-src directive.WebView Android: WebView Android 59 and higher skips the deprecated child-src directive.
http.headers.Content-Security-Policy.worker_support Safari9/20/2016 Edge1/15/20201212
http.headers.Content-Security-Policy-Report-Only 📋Safari10/22/2013 Edge8/2/20161015
http.headers.Content-Type 📋Safari6/23/2003 Edge7/29/20154419
http.headers.Cookie 📋Safari6/23/2003 Edge7/29/20154419
Safari: Cookies with Secure flag are not sent to unsecured http://localhost/ endpoints. See bug 281149.Safari on iOS: Cookies with Secure flag are not sent to unsecured http://localhost/ endpoints. See bug 281149.WebView on iOS: Cookies with Secure flag are not sent to unsecured http://localhost/ endpoints. See bug 281149.
http.headers.Cross-Origin-Embedder-Policy 📋Edge5/21/2020 Safari12/13/2021571
http.headers.Cross-Origin-Opener-Policy 📋Edge5/21/2020 Safari12/13/2021571
http.headers.Cross-Origin-Opener-Policy.noopener-allow-popups 📋Edge11/14/2024 Safari3/31/2025137
http.headers.Cross-Origin-Resource-Policy 📋Safari9/17/2018 Edge1/15/2020485
Chrome: Until version 75, downloads for files with this header would fail in Chrome. See bug 41452948.Chrome: From version 80 to 85, linearized PDFs served inline with this header fail to render properly. See bug 40127935. From version 86, partial PDF loading is disabled.Chrome Android: Until version 75, downloads for files with this header would fail in Chrome Android. See bug 41452948.Chrome Android: From version 80 to 85, linearized PDFs served inline with this header fail to render properly. See bug 40127935. From version 86, partial PDF loading is disabled.Quest Browser: Until version 7.0, downloads for files with this header would fail in Quest Browser. See bug 41452948.Quest Browser: From version 9.0 to 85, linearized PDFs served inline with this header fail to render properly. See bug 40127935. From version 12.0, partial PDF loading is disabled.Opera: Until version 62, downloads for files with this header would fail in Opera. See bug 41452948.Opera: From version 67 to 85, linearized PDFs served inline with this header fail to render properly. See bug 40127935. From version 72, partial PDF loading is disabled.Opera Android: Until version 54, downloads for files with this header would fail in Opera Android. See bug 41452948.Opera Android: From version 57 to 85, linearized PDFs served inline with this header fail to render properly. See bug 40127935. From version 61, partial PDF loading is disabled.WebView Android: Until version 75, downloads for files with this header would fail in WebView Android. See bug 41452948.WebView Android: From version 80 to 85, linearized PDFs served inline with this header fail to render properly. See bug 40127935. From version 86, partial PDF loading is disabled.
http.headers.Date 📋Safari6/23/2003 Edge7/29/20154419
http.headers.ETag 📋Safari6/23/2003 Edge7/29/20154419
http.headers.Expires 📋Safari6/23/2003 Edge7/29/20154419
http.headers.From 📋Safari6/23/2003 Edge7/29/20154419
http.headers.Host 📋Safari6/23/2003 Edge7/29/20154419
http.headers.If-Match 📋Safari6/23/2003 Edge7/29/20154419
http.headers.If-Modified-Since 📋Safari6/23/2003 Edge7/29/20154419
http.headers.If-None-Match 📋Safari6/23/2003 Edge7/29/20154419
http.headers.If-Range 📋Safari6/23/2003 Edge7/29/20154419
http.headers.If-Unmodified-Since 📋Safari6/23/2003 Edge7/29/20154419
http.headers.Keep-Alive 📋Safari6/23/2003 Edge7/29/20154419
http.headers.Last-Modified 📋Safari6/23/2003 Edge7/29/20154419
http.headers.Link 📋Edge6/23/2022 Safari9/18/2023452
http.headers.Link.fetchpriority 📋Edge6/23/2022 Safari12/11/2023536
http.headers.Location 📋Safari6/23/2003 Edge7/29/20154419
http.headers.Origin 📋Safari6/23/2003 Edge1/15/20206050
Edge: Not sent with POST requestsFirefox: Not sent with POST requests, see bug 446344.Firefox for Android: Not sent with POST requests, see bug 446344.
http.headers.Pragma 📋Safari6/23/2003 Edge7/29/20154419
http.headers.Proxy-Authenticate 📋Safari6/23/2003 Edge7/29/20154419
http.headers.Range 📋Safari6/23/2003 Edge7/29/20154419
http.headers.Range.cors_safe Edge3/3/2022 Safari9/12/2022193
http.headers.Referer 📋Safari6/23/2003 Edge7/29/20154419
http.headers.Referer.length_limit_4096B Edge1/15/2020 Safari9/16/2020245
http.headers.Referrer-Policy 📋Safari4/12/2018 Edge1/15/2020643
http.headers.Referrer-Policy.default_strict-origin-when-cross-origin Edge8/27/2020 Safari9/20/2021389
http.headers.Referrer-Policy.same-origin Safari4/12/2018 Edge1/15/2020643
http.headers.Referrer-Policy.strict-origin Safari4/12/2018 Edge1/15/2020643
http.headers.Referrer-Policy.strict-origin-when-cross-origin Safari4/12/2018 Edge1/15/2020643
http.headers.Refresh 📋Safari6/23/2003 Edge7/29/20154419
Firefox: From version 136 the HTTP Referer header is sent following a refresh that redirects to another page (if permitted)Firefox for Android: From version 136 the HTTP Referer header is sent following a refresh that redirects to another page (if permitted)
http.headers.Reporting-Endpoints 📋Edge11/19/2021 Safari3/27/2023493
http.headers.Sec-Fetch-Dest 📋Edge2/7/2020 Safari3/27/20231144
http.headers.Sec-Fetch-Mode 📋Edge1/15/2020 Safari3/27/20231167
http.headers.Sec-Fetch-Site 📋Edge1/15/2020 Safari3/27/20231167
http.headers.Sec-Purpose.speculationrules Edge2/9/2023 Safari12/12/20251037
http.headers.Sec-Speculation-Tags 📋Edge5/1/2025 Safari12/12/2025225
http.headers.Sec-WebSocket-Accept 📋Safari7/25/2012 Edge7/29/20151099
http.headers.Sec-WebSocket-Extensions 📋Safari7/25/2012 Edge7/29/20151099
http.headers.Sec-WebSocket-Key 📋Safari7/25/2012 Edge7/29/20151099
http.headers.Sec-WebSocket-Protocol 📋Safari7/25/2012 Edge7/29/20151099
http.headers.Sec-WebSocket-Version 📋Safari7/25/2012 Edge7/29/20151099
http.headers.Server 📋Safari6/23/2003 Edge7/29/20154419
http.headers.Server-Timing 📋Edge1/15/2020 Safari3/27/20231167
http.headers.Service-Worker 📋Edge10/17/2017 Safari4/12/2018177
http.headers.Service-Worker-Allowed 📋Edge10/17/2017 Safari4/12/2018177
http.headers.Service-Worker-Navigation-Preload 📋Edge10/2/2018 Safari3/14/20221259
http.headers.Set-Cookie 📋Safari6/23/2003 Edge7/29/20154419
Safari: Cookies with Secure flag are not sent to unsecured http://localhost/ endpoints. See bug 281149.Safari on iOS: Cookies with Secure flag are not sent to unsecured http://localhost/ endpoints. See bug 281149.WebView on iOS: Cookies with Secure flag are not sent to unsecured http://localhost/ endpoints. See bug 281149.
http.headers.Set-Cookie.HttpOnly Safari6/7/2010 Edge7/29/20151878
http.headers.Set-Cookie.Max-Age Safari6/23/2003 Edge7/29/20154419
http.headers.Set-Cookie.Partitioned 📋Edge6/2/2023 Safari12/12/2025924
http.headers.Set-Cookie.SameSite 📋Edge10/17/2017 Safari9/19/2019702
Safari: Safari 13 on macOS 10.14 (Mojave), treats SameSite=None and invalid values as Strict. This is fixed in version 10.15 (Catalina) and later.Safari: Treats SameSite=None and invalid values as Strict in macOS before 10.15 Catalina. See bug 198181.Safari on iOS: Treats SameSite=None and invalid values as Strict in iOS before 13. See bug 198181.WebView on iOS: Treats SameSite=None and invalid values as Strict in iOS before 13. See bug 198181.
http.headers.Set-Cookie.SameSite.Lax Edge10/17/2017 Safari9/17/2018335
http.headers.Set-Cookie.SameSite.None Edge10/17/2017 Safari9/19/2019702
Chrome: Rejects cookies with SameSite=None. See SameSite=None: Known Incompatible Clients.Chrome Android: Rejects cookies with SameSite=None. See SameSite=None: Known Incompatible Clients.Quest Browser: Rejects cookies with SameSite=None. See SameSite=None: Known Incompatible Clients.Opera: Rejects cookies with SameSite=None. See SameSite=None: Known Incompatible Clients.Opera Android: Rejects cookies with SameSite=None. See SameSite=None: Known Incompatible Clients.Safari: Not supported before macOS version 10.15 (Catalina).Samsung Internet: Rejects cookies with SameSite=None. See SameSite=None: Known Incompatible Clients.WebView Android: Rejects cookies with SameSite=None. See SameSite=None: Known Incompatible Clients.
http.headers.Set-Cookie.SameSite.Strict Edge10/17/2017 Safari9/17/2018335
http.headers.Set-Cookie.host_secure_prefixes Safari9/19/2019 Edge1/15/2020118
http.headers.SourceMap 📋Safari10/22/2013 Edge1/15/20202276
Chrome: Not supported for ECMAScript Modules (<script type="module">). See bug 40854862.Chrome Android: Not supported for ECMAScript Modules (<script type="module">). See bug 40854862.Edge: Not supported for ECMAScript Modules (<script type="module">). See bug 40854862.Quest Browser: Not supported for ECMAScript Modules (<script type="module">). See bug 40854862.Opera: Not supported for ECMAScript Modules (<script type="module">). See bug 40854862.Opera Android: Not supported for ECMAScript Modules (<script type="module">). See bug 40854862.Samsung Internet: Not supported for ECMAScript Modules (<script type="module">). See bug 40854862.WebView Android: Not supported for ECMAScript Modules (<script type="module">). See bug 40854862.
http.headers.Speculation-Rules 📋Edge1/25/2024 Safari12/12/2025687
http.headers.Strict-Transport-Security 📋Safari10/22/2013 Edge7/29/2015645
http.headers.TE 📋Safari6/23/2003 Edge7/29/20154419
http.headers.Timing-Allow-Origin 📋Safari9/19/2017 Edge1/15/2020848
http.headers.Transfer-Encoding 📋Safari6/23/2003 Edge7/29/20154419
http.headers.Upgrade 📋Safari6/7/2010 Edge7/29/20151878
http.headers.Upgrade-Insecure-Requests 📋Safari3/27/2017 Edge4/30/2018399
http.headers.User-Agent 📋Safari6/23/2003 Edge7/29/20154419
http.headers.Vary 📋Safari6/23/2003 Edge7/29/20154419
http.headers.Via 📋Safari6/23/2003 Edge7/29/20154419
http.headers.WWW-Authenticate 📋Safari6/23/2003 Edge7/29/20154419
http.headers.WWW-Authenticate.Basic 📋Safari6/23/2003 Edge7/29/20154419
http.headers.WWW-Authenticate.Digest 📋Safari6/23/2003 Edge7/29/20154419
http.headers.WWW-Authenticate.Digest.md5 Safari6/23/2003 Edge7/29/20154419
http.headers.WWW-Authenticate.NTLM Safari10/22/2013 Edge1/15/20202276
http.headers.WWW-Authenticate.Negotiate 📋Safari10/22/2013 Edge1/15/20202276
http.headers.Warning 📋Safari6/23/2003 Edge7/29/20154419
http.headers.X-Content-Type-Options 📋Edge7/29/2015 Safari9/19/2017783
Chrome: Not supported for stylesheets.Chrome Android: Not supported for stylesheets.Opera: Not supported for stylesheets.Opera Android: Not supported for stylesheets.Samsung Internet: Not supported for stylesheets.WebView Android: Not supported for stylesheets.
http.headers.X-Frame-Options 📋Safari6/8/2009 Edge7/29/20152242
http.headers.X-Frame-Options.SAMEORIGIN Safari6/8/2009 Edge7/29/20152242
Chrome: Starting in Chrome 61, this applies to all of a frame's ancestors.Chrome Android: Starting in Chrome Android 61, this applies to all of a frame's ancestors.Firefox: Starting in Firefox 59, this applies to all of a frame's ancestors.Firefox for Android: Starting in Firefox for Android 59, this applies to all of a frame's ancestors.Quest Browser: Starting in Quest Browser 5.0, this applies to all of a frame's ancestors.Opera: Starting in Opera 48, this applies to all of a frame's ancestors.Opera Android: Starting in Opera Android 45, this applies to all of a frame's ancestors.Samsung Internet: Starting in Samsung Internet 8.0, this applies to all of a frame's ancestors.WebView Android: Starting in WebView Android 61, this applies to all of a frame's ancestors.
http.methods.CONNECT 📋Safari6/23/2003 Edge7/29/20154419
http.methods.DELETE 📋Safari6/23/2003 Edge7/29/20154419
http.methods.GET 📋Safari6/23/2003 Edge7/29/20154419
http.methods.HEAD 📋Safari6/23/2003 Edge7/29/20154419
http.methods.OPTIONS 📋Safari6/23/2003 Edge7/29/20154419
http.methods.POST 📋Safari6/23/2003 Edge7/29/20154419
http.methods.PUT 📋Safari6/23/2003 Edge7/29/20154419
http.mixed-content 📋Safari3/21/2016 Edge1/15/20201395
http.mixed-content.blockable_mixed_content 📋Safari3/21/2016 Edge1/15/20201395
Chrome: From version 79 blocks iframes, scripts, and stylesheets.Chrome Android: From version 79 blocks iframes, scripts, and stylesheets.Edge: From version 79 blocks iframes, scripts, and stylesheets.Quest Browser: From version 8.0 blocks iframes, scripts, and stylesheets.Opera: From version 66 blocks iframes, scripts, and stylesheets.Opera Android: From version 57 blocks iframes, scripts, and stylesheets.Samsung Internet: From version 12.0 blocks iframes, scripts, and stylesheets.WebView Android: From version 79 blocks iframes, scripts, and stylesheets.
http.status.103 📋Edge6/23/2022 Safari9/18/2023452
Chrome: Supported in HTTP/2 and later only.Chrome Android: Supported in HTTP/2 and later only.Edge: Supported in HTTP/2 and later only.Quest Browser: Supported in HTTP/2 and later only.Opera: Supported in HTTP/2 and later only.Opera Android: Supported in HTTP/2 and later only.Safari: Supported in HTTP/2 and later only.Safari on iOS: Supported in HTTP/2 and later only.Samsung Internet: Supported in HTTP/2 and later only.WebView Android: Supported in HTTP/2 and later only.WebView on iOS: Supported in HTTP/2 and later only.
http.status.103.preconnect Edge6/23/2022 Safari9/18/2023452
http.status.308 📋Safari10/22/2013 Edge7/29/2015645
Internet Explorer: Does not work below Windows 10.