Field Name,Status,Structured Type,Reference,Comments
A-IM,permanent,,[RFC 3229: Delta encoding in HTTP],
Accept,permanent,,"[RFC 9110, Section 12.5.1: HTTP Semantics]",
Accept-Additions,permanent,,[RFC 2324: Hyper Text Coffee Pot Control Protocol (HTCPCP/1.0)],
Accept-CH,permanent,List,"[RFC 8942, Section 3.1: HTTP Client Hints]",
Accept-Charset,deprecated,,"[RFC 9110, Section 12.5.2: HTTP Semantics]",
Accept-Datetime,permanent,,[RFC 7089: HTTP Framework for Time-Based Access to Resource States -- Memento],
Accept-Encoding,permanent,,"[RFC 9110, Section 12.5.3: HTTP Semantics]",
Accept-Features,permanent,,[RFC 2295: Transparent Content Negotiation in HTTP],
Accept-Language,permanent,,"[RFC 9110, Section 12.5.4: HTTP Semantics]",
Accept-Patch,permanent,,[RFC 5789: PATCH Method for HTTP],
Accept-Post,permanent,,[Linked Data Platform 1.0],
Accept-Query,permanent,List,"[RFC-ietf-httpbis-safe-method-w-body-14, Section 3: The HTTP QUERY Method]",
Accept-Ranges,permanent,,"[RFC 9110, Section 14.3: HTTP Semantics]",
Accept-Signature,permanent,,"[RFC 9421, Section 5.1: HTTP Message Signatures]",
Access-Control,obsoleted,,[Access Control for Cross-site Requests],
Access-Control-Allow-Credentials,permanent,,[Fetch],
Access-Control-Allow-Headers,permanent,,[Fetch],
Access-Control-Allow-Methods,permanent,,[Fetch],
Access-Control-Allow-Origin,permanent,,[Fetch],
Access-Control-Expose-Headers,permanent,,[Fetch],
Access-Control-Max-Age,permanent,,[Fetch],
Access-Control-Request-Headers,permanent,,[Fetch],
Access-Control-Request-Method,permanent,,[Fetch],
Activate-Storage-Access,provisional,Item,[https://privacycg.github.io/storage-access-headers],
Age,permanent,,"[RFC 9111, Section 5.1: HTTP Caching]",
Allow,permanent,,"[RFC 9110, Section 10.2.1: HTTP Semantics]",
ALPN,permanent,,"[RFC 7639, Section 2: The ALPN HTTP Header Field]",
Alt-Svc,permanent,,[RFC 7838: HTTP Alternative Services],
Alt-Used,permanent,,[RFC 7838: HTTP Alternative Services],
Alternates,permanent,,[RFC 2295: Transparent Content Negotiation in HTTP],
AMP-Cache-Transform,provisional,,[AMP-Cache-Transform HTTP request header],
Apply-To-Redirect-Ref,permanent,,[RFC 4437: Web Distributed Authoring and Versioning (WebDAV) Redirect Reference Resources],
Authentication-Control,permanent,,"[RFC 8053, Section 4: HTTP Authentication Extensions for Interactive Clients]",
Authentication-Info,permanent,,"[RFC 9110, Section 11.6.3: HTTP Semantics]",
Authorization,permanent,,"[RFC 9110, Section 11.6.2: HTTP Semantics]",
Available-Dictionary,permanent,,"[RFC 9842, Section 2.2: Compression Dictionary Transport]",
C-Ext,obsoleted,,[RFC 2774: An HTTP Extension Framework],[Status change of HTTP experiments to Historic]
C-Man,obsoleted,,[RFC 2774: An HTTP Extension Framework],[Status change of HTTP experiments to Historic]
C-Opt,obsoleted,,[RFC 2774: An HTTP Extension Framework],[Status change of HTTP experiments to Historic]
C-PEP,obsoleted,,[PEP - an Extension Mechanism for HTTP],[Status change of HTTP experiments to Historic]
C-PEP-Info,deprecated,,[PEP - an Extension Mechanism for HTTP],[Status change of HTTP experiments to Historic]
Cache-Control,permanent,,"[RFC 9111, Section 5.2: HTTP Caching]",
Cache-Group-Invalidation,permanent,,[RFC9875: HTTP Cache Groups],
Cache-Groups,permanent,,[RFC9875: HTTP Cache Groups],
Cache-Status,permanent,List,[RFC 9211: The Cache-Status HTTP Response Header Field],
Cal-Managed-ID,permanent,,"[RFC 8607, Section 5.1: Calendaring Extensions to WebDAV (CalDAV): Managed Attachments]",
CalDAV-Timezones,permanent,,"[RFC 7809, Section 7.1: Calendaring Extensions to WebDAV (CalDAV): Time Zones by Reference]",
Capsule-Protocol,permanent,,[RFC 9297: HTTP Datagrams and the Capsule Protocol],
CDN-Cache-Control,permanent,Dictionary,[RFC 9213: Targeted HTTP Cache Control],Cache directives targeted at content delivery networks
CDN-Loop,permanent,,[RFC 8586: Loop Detection in Content Delivery Networks (CDNs)],
Cert-Not-After,permanent,,"[RFC 8739, Section 3.3: Support for Short-Term, Automatically Renewed (STAR) Certificates in the Automated Certificate Management Environment (ACME)]",
Cert-Not-Before,permanent,,"[RFC 8739, Section 3.3: Support for Short-Term, Automatically Renewed (STAR) Certificates in the Automated Certificate Management Environment (ACME)]",
Clear-Site-Data,permanent,,[Clear Site Data],
Client-Cert,permanent,Item,"[RFC 9440, Section 2: Client-Cert HTTP Header Field]",
Client-Cert-Chain,permanent,List,"[RFC 9440, Section 2: Client-Cert HTTP Header Field]",
Close,permanent,,"[RFC 9112, Section 9.6: HTTP/1.1]",(reserved)
CMCD-Object,provisional,,[CTA][CTA-5004 Common Media Client Data],
CMCD-Request,provisional,,[CTA][CTA-5004 Common Media Client Data],
CMCD-Session,provisional,,[CTA][CTA-5004 Common Media Client Data],
CMCD-Status,provisional,,[CTA][CTA-5004 Common Media Client Data],
CMSD-Dynamic,provisional,,[CTA][CTA-5006 Common Media Server Data (CMSD)],
CMSD-Static,provisional,,[CTA][CTA-5006 Common Media Server Data (CMSD)],
Concealed-Auth-Export,permanent,Item,[RFC 9729: The Concealed HTTP Authentication Scheme],
Configuration-Context,provisional,,[OSLC Configuration Management Version 1.0. Part 3: Configuration Specification],
Connection,permanent,,"[RFC 9110, Section 7.6.1: HTTP Semantics]",
Content-Base,obsoleted,,[RFC 2068: Hypertext Transfer Protocol -- HTTP/1.1],Obsoleted by [RFC 2616: Hypertext Transfer Protocol -- HTTP/1.1]
Content-Digest,permanent,,"[RFC 9530, Section 2: Digest Fields]",
Content-Disposition,permanent,,[RFC 6266: Use of the Content-Disposition Header Field in the Hypertext Transfer Protocol (HTTP)],
Content-Encoding,permanent,,"[RFC 9110, Section 8.4: HTTP Semantics]",
Content-ID,deprecated,,[The HTTP Distribution and Replication Protocol],
Content-Language,permanent,,"[RFC 9110, Section 8.5: HTTP Semantics]",
Content-Length,permanent,,"[RFC 9110, Section 8.6: HTTP Semantics]",
Content-Location,permanent,,"[RFC 9110, Section 8.7: HTTP Semantics]",
Content-MD5,obsoleted,,"[RFC 2616, Section 14.15: Hypertext Transfer Protocol -- HTTP/1.1]","Obsoleted by [RFC 7231, Appendix B: Hypertext Transfer Protocol (HTTP/1.1): Semantics and Content]"
Content-Range,permanent,,"[RFC 9110, Section 14.4: HTTP Semantics]",
Content-Script-Type,obsoleted,,[HTML 4.01 Specification],
Content-Security-Policy,permanent,,[Content Security Policy Level 3],
Content-Security-Policy-Report-Only,permanent,,[Content Security Policy Level 3],
Content-Style-Type,obsoleted,,[HTML 4.01 Specification],
Content-Type,permanent,,"[RFC 9110, Section 8.3: HTTP Semantics]",
Content-Version,obsoleted,,[RFC 2068: Hypertext Transfer Protocol -- HTTP/1.1],
Cookie,permanent,,"[RFC-ietf-httpbis-rfc6265bis-22, Section 5.8.1: Cookies: HTTP State Management Mechanism]",
Cookie2,obsoleted,,[RFC 2965: HTTP State Management Mechanism],Obsoleted by [RFC 6265: HTTP State Management Mechanism]
Cross-Origin-Embedder-Policy,permanent,Item,[HTML],
Cross-Origin-Embedder-Policy-Report-Only,permanent,Item,[HTML],
Cross-Origin-Opener-Policy,permanent,Item,[HTML],
Cross-Origin-Opener-Policy-Report-Only,permanent,Item,[HTML],
Cross-Origin-Resource-Policy,permanent,,[Fetch],
CTA-Common-Access-Token,provisional,,[CTA][Chris_Lemmons],
DASL,permanent,,[RFC 5323: Web Distributed Authoring and Versioning (WebDAV) SEARCH],
Date,permanent,,"[RFC 9110, Section 6.6.1: HTTP Semantics]",
DAV,permanent,,[RFC 4918: HTTP Extensions for Web Distributed Authoring and Versioning (WebDAV)],
Default-Style,obsoleted,,[HTML 4.01 Specification],
Delta-Base,permanent,,[RFC 3229: Delta encoding in HTTP],
Deprecation,permanent,Item,"[RFC 9745, Section 2: The Deprecation HTTP Response Header Field]",
Depth,permanent,,[RFC 4918: HTTP Extensions for Web Distributed Authoring and Versioning (WebDAV)],
Derived-From,obsoleted,,[RFC 2068: Hypertext Transfer Protocol -- HTTP/1.1],
Destination,permanent,,[RFC 4918: HTTP Extensions for Web Distributed Authoring and Versioning (WebDAV)],
Detached-JWS,permanent,,[RFC 9635: Grant Negotiation and Authorization Protocol (GNAP)],
Differential-ID,deprecated,,[The HTTP Distribution and Replication Protocol],
Dictionary-ID,permanent,,"[RFC 9842, Section 2.3: Compression Dictionary Transport]",
Digest,obsoleted,,[RFC 3230: Instance Digests in HTTP],"Obsoleted by [RFC 9530, Section 1.3: Digest Fields]"
DPoP,permanent,,[RFC 9449: OAuth 2.0 Demonstrating Proof of Possession (DPoP)],
DPoP-Nonce,permanent,,[RFC 9449: OAuth 2.0 Demonstrating Proof of Possession (DPoP)],
Early-Data,permanent,,[RFC 8470: Using Early Data in HTTP],
EDIINT-Features,provisional,,[RFC 6017: Electronic Data Interchange - Internet Integration (EDIINT) Features Header Field],
ETag,permanent,,"[RFC 9110, Section 8.8.3: HTTP Semantics]",
Expect,permanent,,"[RFC 9110, Section 10.1.1: HTTP Semantics]",
Expect-CT,deprecated,,[RFC 9163: Expect-CT Extension for HTTP],"Obsoleted by [IESG]
        [HTTPBIS]"
Expires,permanent,,"[RFC 9111, Section 5.3: HTTP Caching]",
Ext,obsoleted,,[RFC 2774: An HTTP Extension Framework],[Status change of HTTP experiments to Historic]
Forwarded,permanent,,[RFC 7239: Forwarded HTTP Extension],
From,permanent,,"[RFC 9110, Section 10.1.2: HTTP Semantics]",
GetProfile,obsoleted,,[Implementation of OPS Over HTTP],
Hobareg,permanent,,"[RFC 7486, Section 6.1.1: HTTP Origin-Bound Authentication (HOBA)]",
Host,permanent,,"[RFC 9110, Section 7.2: HTTP Semantics]",
HTTP2-Settings,obsoleted,,"[RFC 7540, Section 3.2.1: Hypertext Transfer Protocol Version 2 (HTTP/2)]",Obsolete; see Section 11.1 of [RFC9113]
If,permanent,,[RFC 4918: HTTP Extensions for Web Distributed Authoring and Versioning (WebDAV)],
If-Match,permanent,,"[RFC 9110, Section 13.1.1: HTTP Semantics]",
If-Modified-Since,permanent,,"[RFC 9110, Section 13.1.3: HTTP Semantics]",
If-None-Match,permanent,,"[RFC 9110, Section 13.1.2: HTTP Semantics]",
If-Range,permanent,,"[RFC 9110, Section 13.1.5: HTTP Semantics]",
If-Schedule-Tag-Match,permanent,,[ RFC 6338: Scheduling Extensions to CalDAV],
If-Unmodified-Since,permanent,,"[RFC 9110, Section 13.1.4: HTTP Semantics]",
IM,permanent,,[RFC 3229: Delta encoding in HTTP],
Include-Referred-Token-Binding-ID,permanent,,[RFC 8473: Token Binding over HTTP],
Isolation,provisional,,[OData Version 4.01 Part 1: Protocol][OASIS][Chet_Ensign],
Keep-Alive,permanent,,[RFC 2068: Hypertext Transfer Protocol -- HTTP/1.1],
Label,permanent,,[RFC 3253: Versioning Extensions to WebDAV: (Web Distributed Authoring and Versioning)],
Last-Event-ID,permanent,,[HTML],
Last-Modified,permanent,,"[RFC 9110, Section 8.8.2: HTTP Semantics]",
Link,permanent,,[RFC 8288: Web Linking],
Link-Template,permanent,,[RFC 9652: The Link-Template HTTP Header Field],
Location,permanent,,"[RFC 9110, Section 10.2.2: HTTP Semantics]",
Lock-Token,permanent,,[RFC 4918: HTTP Extensions for Web Distributed Authoring and Versioning (WebDAV)],
Man,obsoleted,,[RFC 2774: An HTTP Extension Framework],[Status change of HTTP experiments to Historic]
Max-Forwards,permanent,,"[RFC 9110, Section 7.6.2: HTTP Semantics]",
Memento-Datetime,permanent,,[RFC 7089: HTTP Framework for Time-Based Access to Resource States -- Memento],
Meter,permanent,,[RFC 2227: Simple Hit-Metering and Usage-Limiting for HTTP],
Method-Check,obsoleted,,[Access Control for Cross-site Requests],
Method-Check-Expires,obsoleted,,[Access Control for Cross-site Requests],
MIME-Version,permanent,,"[RFC 9112, Appendix B.1: HTTP/1.1]",
Negotiate,permanent,,[RFC 2295: Transparent Content Negotiation in HTTP],
NEL,permanent,,[Network Error Logging],
OData-EntityId,permanent,,[OData Version 4.01 Part 1: Protocol][OASIS][Chet_Ensign],
OData-Isolation,permanent,,[OData Version 4.01 Part 1: Protocol][OASIS][Chet_Ensign],
OData-MaxVersion,permanent,,[OData Version 4.01 Part 1: Protocol][OASIS][Chet_Ensign],
OData-Version,permanent,,[OData Version 4.01 Part 1: Protocol][OASIS][Chet_Ensign],
Opt,obsoleted,,[RFC 2774: An HTTP Extension Framework],[Status change of HTTP experiments to Historic]
Optional-WWW-Authenticate,permanent,,"[RFC 8053, Section 3: HTTP Authentication Extensions for Interactive Clients]",
Ordering-Type,permanent,,[RFC 3648: Web Distributed Authoring and Versioning (WebDAV) Ordered Collections Protocol],
Origin,permanent,,[RFC 6454: The Web Origin Concept],
Origin-Agent-Cluster,permanent,Item,[HTML],
OSCORE,permanent,,"[RFC 8613, Section 11.1: Object Security for Constrained RESTful Environments (OSCORE)]",
OSLC-Core-Version,permanent,,[OASIS Project Specification 01][OASIS][Chet_Ensign],
Overwrite,permanent,,[RFC 4918: HTTP Extensions for Web Distributed Authoring and Versioning (WebDAV)],
P3P,obsoleted,,[The Platform for Privacy Preferences 1.0 (P3P1.0) Specification],
PEP,obsoleted,,[PEP - an Extension Mechanism for HTTP],
PEP-Info,obsoleted,,[PEP - an Extension Mechanism for HTTP],
Permissions-Policy,provisional,,[Permissions Policy],
PICS-Label,obsoleted,,[PICS Label Distribution Label Syntax and Communication Protocols],
Ping-From,permanent,,[HTML],
Ping-To,permanent,,[HTML],
Position,permanent,,[RFC 3648: Web Distributed Authoring and Versioning (WebDAV) Ordered Collections Protocol],
Pragma,deprecated,,"[RFC 9111, Section 5.4: HTTP Caching]",
Prefer,permanent,,[RFC 7240: Prefer Header for HTTP],
Preference-Applied,permanent,,[RFC 7240: Prefer Header for HTTP],
Priority,permanent,Dictionary,[RFC 9218: Extensible Prioritization Scheme for HTTP],
ProfileObject,obsoleted,,[Implementation of OPS Over HTTP],
Protocol,obsoleted,,[PICS Label Distribution Label Syntax and Communication Protocols],
Protocol-Info,deprecated,,[White Paper: Joint Electronic Payment Initiative],
Protocol-Query,deprecated,,[White Paper: Joint Electronic Payment Initiative],
Protocol-Request,obsoleted,,[PICS Label Distribution Label Syntax and Communication Protocols],
Proxy-Authenticate,permanent,,"[RFC 9110, Section 11.7.1: HTTP Semantics]",
Proxy-Authentication-Info,permanent,,"[RFC 9110, Section 11.7.3: HTTP Semantics]",
Proxy-Authorization,permanent,,"[RFC 9110, Section 11.7.2: HTTP Semantics]",
Proxy-Features,obsoleted,,[Notification for Proxy Caches],
Proxy-Instruction,obsoleted,,[Notification for Proxy Caches],
Proxy-Status,permanent,List,[RFC 9209: The Proxy-Status HTTP Response Header Field],
Public,obsoleted,,[RFC 2068: Hypertext Transfer Protocol -- HTTP/1.1],
Public-Key-Pins,permanent,,[RFC 7469: Public Key Pinning Extension for HTTP],
Public-Key-Pins-Report-Only,permanent,,[RFC 7469: Public Key Pinning Extension for HTTP],
Range,permanent,,"[RFC 9110, Section 14.2: HTTP Semantics]",
Redirect-Ref,permanent,,[RFC 4437: Web Distributed Authoring and Versioning (WebDAV) Redirect Reference Resources],
Referer,permanent,,"[RFC 9110, Section 10.1.3: HTTP Semantics]",
Referer-Root,obsoleted,,[Access Control for Cross-site Requests],
Referrer-Policy,permanent,,[Referrer Policy],The header name does not share the HTTP Referer header's misspelling.
Refresh,permanent,,[HTML],
Repeatability-Client-ID,provisional,,[Repeatable Requests Version 1.0][OASIS][Chet_Ensign],
Repeatability-First-Sent,provisional,,[Repeatable Requests Version 1.0][OASIS][Chet_Ensign],
Repeatability-Request-ID,provisional,,[Repeatable Requests Version 1.0][OASIS][Chet_Ensign],
Repeatability-Result,provisional,,[Repeatable Requests Version 1.0][OASIS][Chet_Ensign],
Replay-Nonce,permanent,,"[RFC 8555, Section 6.5.1: Automatic Certificate Management Environment (ACME)]",
Reporting-Endpoints,provisional,,[Reporting API],
Repr-Digest,permanent,,"[RFC 9530, Section 3: Digest Fields]",
Retry-After,permanent,,"[RFC 9110, Section 10.2.3: HTTP Semantics]",
Safe,obsoleted,,[RFC 2310: The Safe Response Header Field],[Status change of HTTP experiments to Historic]
Schedule-Reply,permanent,,[RFC 6638: Scheduling Extensions to CalDAV],
Schedule-Tag,permanent,,[RFC 6338: Scheduling Extensions to CalDAV],
Sec-Fetch-Dest,Permanent,Item,[https://www.w3.org/TR/fetch-metadata/#sec-fetch-dest-header],
Sec-Fetch-Mode,Permanent,Item,[https://www.w3.org/TR/fetch-metadata/#sec-fetch-mode-header],
Sec-Fetch-Site,Permanent,Item,[https://www.w3.org/TR/fetch-metadata/#sec-fetch-site-header],
Sec-Fetch-Storage-Access,provisional,Token,[https://privacycg.github.io/storage-access-headers],
Sec-Fetch-User,Permanent,Item,[https://www.w3.org/TR/fetch-metadata/#sec-fetch-user-header],
Sec-GPC,provisional,,[Global Privacy Control (GPC)],
Sec-Purpose,permanent,,[Fetch],Intended to replace the (not registered) Purpose and x-moz headers.
Sec-Token-Binding,permanent,,[RFC 8473: Token Binding over HTTP],
Sec-WebSocket-Accept,permanent,,[RFC 6455: The WebSocket Protocol],
Sec-WebSocket-Extensions,permanent,,[RFC 6455: The WebSocket Protocol],
Sec-WebSocket-Key,permanent,,[RFC 6455: The WebSocket Protocol],
Sec-WebSocket-Protocol,permanent,,[RFC 6455: The WebSocket Protocol],
Sec-WebSocket-Version,permanent,,[RFC 6455: The WebSocket Protocol],
Security-Scheme,obsoleted,,[RFC 2660: The Secure HyperText Transfer Protocol],[Status change of HTTP experiments to Historic]
Server,permanent,,"[RFC 9110, Section 10.2.4: HTTP Semantics]",
Server-Timing,permanent,,[Server Timing],
Set-Cookie,permanent,,"[RFC-ietf-httpbis-rfc6265bis-22, Section 5.8.1: Cookies: HTTP State Management Mechanism]",
Set-Cookie2,obsoleted,,[RFC 2965: HTTP State Management Mechanism],Obsoleted by [RFC 6265: HTTP State Management Mechanism]
Set-Txn,permanent,,"[RFC-ietf-scim-events-15, Section 3: SCIM Profile for Security Event Tokens]",
SetProfile,obsoleted,,[Implementation of OPS Over HTTP],
Signature,permanent,,"[RFC 9421, Section 4.2: HTTP Message Signatures]",
Signature-Input,permanent,,"[RFC 9421, Section 4.1: HTTP Message Signatures]",
SLUG,permanent,,[RFC 5023: The Atom Publishing Protocol],
SoapAction,permanent,,[Simple Object Access Protocol (SOAP) 1.1],
Status-URI,permanent,,[RFC 2518: HTTP Extensions for Distributed Authoring -- WEBDAV],
Strict-Transport-Security,permanent,,[RFC 6797: HTTP Strict Transport Security (HSTS)],
Sunset,permanent,,[RFC 8594: The Sunset HTTP Header Field],
Surrogate-Capability,provisional,,[Edge Architecture Specification],
Surrogate-Control,provisional,,[Edge Architecture Specification],
TCN,permanent,,[RFC 2295: Transparent Content Negotiation in HTTP],
TE,permanent,,"[RFC 9110, Section 10.1.4: HTTP Semantics]",
Timeout,permanent,,[RFC 4918: HTTP Extensions for Web Distributed Authoring and Versioning (WebDAV)],
Timing-Allow-Origin,provisional,,[Resource Timing Level 1],
Topic,permanent,,"[RFC 8030, Section 5.4: Generic Event Delivery Using HTTP Push]",
Traceparent,permanent,,[Trace Context],
Tracestate,permanent,,[Trace Context],
Trailer,permanent,,"[RFC 9110, Section 6.6.2: HTTP Semantics]",
Transfer-Encoding,permanent,,"[RFC 9112, Section 6.1: HTTP Semantics]",
TTL,permanent,,"[RFC 8030, Section 5.2: Generic Event Delivery Using HTTP Push]",
Upgrade,permanent,,"[RFC 9110, Section 7.8: HTTP Semantics]",
Urgency,permanent,,"[RFC 8030, Section 5.3: Generic Event Delivery Using HTTP Push]",
URI,obsoleted,,[RFC 2068: Hypertext Transfer Protocol -- HTTP/1.1],
Use-As-Dictionary,permanent,,"[RFC 9842, Section 2.1: Compression Dictionary Transport]",
User-Agent,permanent,,"[RFC 9110, Section 10.1.5: HTTP Semantics]",
Variant-Vary,permanent,,[RFC 2295: Transparent Content Negotiation in HTTP],
Vary,permanent,,"[RFC 9110, Section 12.5.5: HTTP Semantics]",
Via,permanent,,"[RFC 9110, Section 7.6.3: HTTP Semantics]",
Want-Content-Digest,permanent,,"[RFC 9530, Section 4: Digest Fields]",
Want-Digest,obsoleted,,[RFC 3230: Instance Digests in HTTP],"Obsoleted by [RFC 9530, Section 1.3: Digest Fields]"
Want-Repr-Digest,permanent,,"[RFC 9530, Section 4: Digest Fields]",
Warning,obsoleted,,"[RFC 9111, Section 5.5: HTTP Caching]",
WWW-Authenticate,permanent,,"[RFC 9110, Section 11.6.1: HTTP Semantics]",
X-Content-Type-Options,permanent,,[Fetch],
X-Frame-Options,permanent,,[HTML],
*,permanent,,"[RFC 9110, Section 12.5.5: HTTP Semantics]",(reserved)