Registration of further IMAP/JMAP keywords and mailbox attribute names
draft-ietf-mailmaint-messageflag-mailboxattribute-01
| Document | Type | Active Internet-Draft (mailmaint WG) | |
|---|---|---|---|
| Authors | Neil Jenkins , Daniel Eggert | ||
| Last updated | 2024-12-10 | ||
| Replaces | draft-eggert-mailflagcolors, draft-eggert-messageflag-mailboxattribute, draft-jenkins-mail-keywords | ||
| RFC stream | Internet Engineering Task Force (IETF) | ||
| Intended RFC status | (None) | ||
| Formats | |||
| Additional resources | Mailing list discussion | ||
| Stream | WG state | WG Document | |
| Document shepherd | (None) | ||
| IESG | IESG state | I-D Exists | |
| Consensus boilerplate | Unknown | ||
| Telechat date | (None) | ||
| Responsible AD | (None) | ||
| Send notices to | (None) |
draft-ietf-mailmaint-messageflag-mailboxattribute-01
MailMaint N.M. Jenkins, Ed.
Internet-Draft Fastmail
Intended status: Informational D. Eggert, Ed.
Expires: 12 June 2025 Apple Inc
9 December 2024
Registration of further IMAP/JMAP keywords and mailbox attribute names
draft-ietf-mailmaint-messageflag-mailboxattribute-01
Abstract
This document defines a number of keywords that have been in use by
Fastmail and Apple respectively for some time. It defines their
intended use. Additionally some mailbox names with special meaning
have been in use by Fastmail, and this document defines their
intended use. This document registers all of these names with IANA
to avoid name collisions.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on 12 June 2025.
Copyright Notice
Copyright (c) 2024 IETF Trust and the persons identified as the
document authors. All rights reserved.
Jenkins & Eggert Expires 12 June 2025 [Page 1]
Internet-Draft Further IMAP/JMAP keywords & attributes December 2024
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents (https://trustee.ietf.org/
license-info) in effect on the date of publication of this document.
Please review these documents carefully, as they describe your rights
and restrictions with respect to this document. Code Components
extracted from this document must include Revised BSD License text as
described in Section 4.e of the Trust Legal Provisions and are
provided without warranty as described in the Revised BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Requirements Language . . . . . . . . . . . . . . . . . . . . 4
3. Flag Colors . . . . . . . . . . . . . . . . . . . . . . . . . 4
3.1. Definition of the MailFlagBit Message Keyword . . . . . . 4
3.2. Implementation Notes . . . . . . . . . . . . . . . . . . 5
4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 5
4.1. IMAP/JMAP Keyword Registrations . . . . . . . . . . . . . 5
4.1.1. $notify keyword registration . . . . . . . . . . . . 5
4.1.2. $muted keyword registration . . . . . . . . . . . . . 6
4.1.3. $followed keyword registration . . . . . . . . . . . 7
4.1.4. $memo keyword registration . . . . . . . . . . . . . 7
4.1.5. $hasmemo keyword registration . . . . . . . . . . . . 8
4.1.6. $hasattachment keyword registration . . . . . . . . . 8
4.1.7. $autosent keyword registration . . . . . . . . . . . 9
4.1.8. $unsubscribed keyword registration . . . . . . . . . 9
4.1.9. $canunsubscribe keyword registration . . . . . . . . 10
4.1.10. $imported keyword registration . . . . . . . . . . . 10
4.1.11. $istrusted keyword registration . . . . . . . . . . . 10
4.1.12. $maskedemail keyword registration . . . . . . . . . . 11
4.1.13. $new keyword registration . . . . . . . . . . . . . . 12
4.1.14. $MailFlagBit0 keyword registration . . . . . . . . . 12
4.1.15. $MailFlagBit1 keyword registration . . . . . . . . . 12
4.1.16. $MailFlagBit2 keyword registration . . . . . . . . . 13
4.2. IMAP Mailbox Name Attributes Registrations . . . . . . . 13
4.2.1. Snoozed mailbox name attribute registration . . . . . 13
4.2.2. Scheduled mailbox name attribute registration . . . . 13
4.2.3. Memos mailbox name attribute registration . . . . . . 14
5. Security Considerations . . . . . . . . . . . . . . . . . . . 14
6. References . . . . . . . . . . . . . . . . . . . . . . . . . 14
6.1. Normative References . . . . . . . . . . . . . . . . . . 14
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 15
Jenkins & Eggert Expires 12 June 2025 [Page 2]
Internet-Draft Further IMAP/JMAP keywords & attributes December 2024
1. Introduction
The Internet Message Access Protocol (IMAP) specification [RFC9051]
defines the use of message keywords, and an "IMAP Keywords" registry
is created in [RFC5788]. Similarly [RFC8457] creates an "IMAP
Mailbox Name Attributes Registry".
This document does the following:
* Defines 16 message keywords
- $notify
- $muted
- $followed
- $memo
- $hasmemo
- $hasattachment
- $autosent
- $unsubscribed
- $canunsubscribe
- $imported
- $istrusted
- $maskedemail
- $new
- $MailFlagBit0
- $MailFlagBit1
- $MailFlagBit2
* Defines 3 mailbox name attributes
- Snoozed
- Scheduled
Jenkins & Eggert Expires 12 June 2025 [Page 3]
Internet-Draft Further IMAP/JMAP keywords & attributes December 2024
- Memos
* Registers these in the "IMAP Keywords" registry and "IMAP Mailbox
Name Attributes" registry respectively.
2. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
3. Flag Colors
The Internet Message Access Protocol (IMAP) specification [RFC9051]
defines a \Flagged system flag to mark a message for urgent/special
attention. The new keywords defined in Sections 4.1.14, 4.1.15, and
4.1.16 allow such a flagged message to have that flag be of one of 7
colors.
3.1. Definition of the MailFlagBit Message Keyword
The 3 flag color keywords $MailFlagBit0, $MailFlagBit1, and
$MailFlagBit2 make up a bit pattern that define the color of the flag
as such:
+=======+=======+=======+========+
| Bit 0 | Bit 1 | Bit 2 | Color |
+=======+=======+=======+========+
| 0 | 0 | 0 | red |
+-------+-------+-------+--------+
| 1 | 0 | 0 | orange |
+-------+-------+-------+--------+
| 0 | 1 | 0 | yellow |
+-------+-------+-------+--------+
| 1 | 1 | 1 | green |
+-------+-------+-------+--------+
| 0 | 0 | 1 | blue |
+-------+-------+-------+--------+
| 1 | 0 | 1 | purple |
+-------+-------+-------+--------+
| 0 | 1 | 1 | gray |
+-------+-------+-------+--------+
Table 1: Flag Colors
Jenkins & Eggert Expires 12 June 2025 [Page 4]
Internet-Draft Further IMAP/JMAP keywords & attributes December 2024
These flags SHOULD be ignored if the \Flagged system flag is not set.
If the \Flagged system flag is set, the flagged status MAY be
displayed to the user in the color corresponding to the combination
of the 3 flag color keywords.
3.2. Implementation Notes
A mail client that is aware of these flag color keywords SHOULD clear
all 3 flag color keywords when the user unflags the message, i.e.
when unsetting the \Flagged system flag, all 3 flag color keywords
SHOULD also be unset.
A mail client SHOULD NOT set any of these flags unless the \Flagged
system flag is already set or is being set.
Servers MAY unset these flag color keywords when a client unsets the
\Flagged system flag.
4. IANA Considerations
3 IMAP/JMAP keywords are registered in the IMAP/JMAP keywords
registry, as established in RFC5788.
4.1. IMAP/JMAP Keyword Registrations
4.1.1. $notify keyword registration
IMAP/JMAP keyword name: $notify
Purpose: Indicate to the client that a notification should be shown
for this message.
Private or Shared on a server: SHARED
Is it an advisory keyword or may it cause an automatic action: This
keyword can cause automatic action. On supporting clients, when a
new message is added to the mailstore with this keyword, the
client should show the user a notification.
Mail clients commonly show notifications for new mail, but often
the only option is to show a notification for every message that
arrives in the inbox. This keyword allows the user to create
rules (or the server to automatically determine) specific messages
that should show a notification.
Notifications for these messages may be in addition to
notifications for messages matching other criteria, according to
user preference set on the client.
When/by whom the keyword is set/cleared: This keyword is set by an
Jenkins & Eggert Expires 12 June 2025 [Page 5]
Internet-Draft Further IMAP/JMAP keywords & attributes December 2024
IMAP or JMAP server on delivery when a message meets criteria such
that the user should be shown a notification. It may be cleared
by a client when the user opens, archives, or otherwise interacts
with the message. Other clients connected to the same account may
choose to automatically close the notification if the flag is
cleared.
Related keywords: None
Related IMAP capabilities: None
Security considerations: None
Published specification: This document
Intended usage: COMMON
Scope: BOTH
Owner/Change controller: IESG
4.1.2. $muted keyword registration
IMAP/JMAP keyword name: $muted
Purpose: Indicate to the server that the user is not interested in
future replies to a particular thread.
Private or Shared on a server: SHARED
Is it an advisory keyword or may it cause an automatic action: This
keyword can cause automatic action. On supporting servers, when a
new message arrives that is in the same thread as a message with
this keyword the server may automatically process it in some way
to deprioritise it for the user, for example by moving it to the
archive or trash, or marking it read. The exact action, whether
this is customisable by the user, and interaction with user rules
is vendor specific.
A message is defined to be in the same thread as another if the
server assigns them both the same thread id, as defined in
[RFC8474] Section 5.2 for IMAP or [RFC8621], Section 3 for JMAP.
When/by whom the keyword is set/cleared: This keyword is set by an
IMAP or JMAP client when the user indicates they wish to mute or
unmute a thread. When unmuting a thread, the client must remove
the keyword from every message in the thread that has it.
Related keywords: Mutually exclusive with $followed. If both are
specified on a thread, servers MUST behave as though only
$followed were set.
Related IMAP capabilities: None
Security considerations: Muting a thread can mean a user won't see a
reply. If someone compromises a user's account, they may mute
threads where they don't want the user to see the reply, for
example when sending phishing to the user's contacts. There are
many other ways an attacker with access to the user's mailbox can
also achieve this however, so this is not greatly increasing the
attack surface.
Published specification: This document
Intended usage: COMMON
Jenkins & Eggert Expires 12 June 2025 [Page 6]
Internet-Draft Further IMAP/JMAP keywords & attributes December 2024
Scope: BOTH
Owner/Change controller: IESG
4.1.3. $followed keyword registration
IMAP/JMAP keyword name: $followed
Purpose: Indicate to the server that the user is particularly
interested in future replies to a particular thread.
Private or Shared on a server: SHARED
Is it an advisory keyword or may it cause an automatic action: This
keyword can cause automatic action. On supporting servers, when a
new message arrives that is in the same thread as a message with
this keyword the server may automatically process it in some way
to prioritise it for the user, for example by ignoring rules that
would make it skip the inbox, or automatically adding the $notify
keyword. The exact action, whether this is customisable by the
user, and interaction with user rules is vendor specific.
A message is defined to be in the same thread as another if the
server assigns them both the same thread id, as defined in
[RFC8474] Section 5.2 for IMAP or [RFC8621], Section 3 for JMAP.
When/by whom the keyword is set/cleared: This keyword is set by an
IMAP or JMAP client when the user indicates they wish to follow or
unfollow a thread. When unfollowing a thread, the client must
remove the keyword from every message in the thread that has it.
Related keywords: Mutually exclusive with $muted. If both are
specified on a thread, servers MUST behave as though only
$followed were set.
Related IMAP capabilities: None
Security considerations: None
Published specification: This document
Intended usage: COMMON
Scope: BOTH
Owner/Change controller: IESG
4.1.4. $memo keyword registration
IMAP/JMAP keyword name: $memo
Purpose: Indicate to the client that a message is a note-to-self
from the user regarding another message in the same thread.
Private or Shared on a server: SHARED
Is it an advisory keyword or may it cause an automatic action: This
keyword is advisory.
When/by whom the keyword is set/cleared: This keyword is set by an
IMAP or JMAP client when creating such a message. The message
should otherwise be contructed like a reply to the message to
which this memo is attached (i.e. appropriate Subject and Reply-To
headers set). In supporting clients, messages with this flag may
be presented differently to the user, attached to the message the
Jenkins & Eggert Expires 12 June 2025 [Page 7]
Internet-Draft Further IMAP/JMAP keywords & attributes December 2024
memo is commenting on, and may offer the user the ability to edit
or delete the memo. (As messages are immutable, editing requires
replacing the message.)
Related keywords: The $hasmemo keyword should be set/cleared at the
same time.
Related IMAP capabilities: None
Security considerations: None
Published specification: This document
Intended usage: COMMON
Scope: BOTH
Owner/Change controller: IESG
4.1.5. $hasmemo keyword registration
IMAP/JMAP keyword name: $hasmemo
Purpose: Indicate to the client that a message has an associated
memo with the $memo keyword.
Private or Shared on a server: SHARED
Is it an advisory keyword or may it cause an automatic action: This
keyword is advisory.
When/by whom the keyword is set/cleared: This keyword is set by an
IMAP or JMAP client when creating a memo. The memo gets the $memo
keyword, the message it is a note for gets the $hasmemo keyword.
This keyword can help in searching for messages with memos, or
deciding whether to fetch the whole thread to look for memos when
loading a mailbox.
Related keywords: A message with the $memo keyword should be
created/destroyed at the same time.
Related IMAP capabilities: None
Security considerations: None
Published specification: This document
Intended usage: COMMON
Scope: BOTH
Owner/Change controller: IESG
4.1.6. $hasattachment keyword registration
IMAP/JMAP keyword name: $hasattachment
Purpose: Indicate to the client that a message has an attachment.
Private or Shared on a server: SHARED
Is it an advisory keyword or may it cause an automatic action: This
keyword is advisory.
When/by whom the keyword is set/cleared: This keyword is set by an
IMAP or JMAP server on messages it determines have an attachment.
This can help mailbox clients indicate this to the user without
having to fetch the full message body structure. Over JMAP, the
"hasAttachment" Email property should indicate the same value.
Related keywords: None
Jenkins & Eggert Expires 12 June 2025 [Page 8]
Internet-Draft Further IMAP/JMAP keywords & attributes December 2024
Related IMAP capabilities: None
Security considerations: None
Published specification: This document
Intended usage: COMMON
Scope: BOTH
Owner/Change controller: IESG
4.1.7. $autosent keyword registration
IMAP/JMAP keyword name: $autosent
Purpose: Indicate to the client that a message was sent
automatically as a response due to a user rule or setting.
Private or Shared on a server: SHARED
Is it an advisory keyword or may it cause an automatic action: This
keyword is advisory.
When/by whom the keyword is set/cleared: This keyword is set by an
IMAP or JMAP server on the user's copy of their vacation response
and other automated messages sent on behalf of the user. Clients
may use this to indicate to the user that this message was sent
automatically, as if they have forgotten the rule or vacation
response is set up they may be surprised to see it among their
sent items.
Related keywords: None
Related IMAP capabilities: None
Security considerations: None
Published specification: This document
Intended usage: COMMON
Scope: BOTH
Owner/Change controller: IESG
4.1.8. $unsubscribed keyword registration
IMAP/JMAP keyword name: $unsubscribed
Purpose: Indicate to the client that it has unsubscribed from the
thread this message is on.
Private or Shared on a server: SHARED
Is it an advisory keyword or may it cause an automatic action: This
keyword is advisory.
When/by whom the keyword is set/cleared: This keyword is set by an
IMAP or JMAP client on a message after attempting to unsubscribe
from the mailing list this message came from (e.g., after
attempting RFC8058 one-click List-Unsubscribe). It allows clients
to remind the user that they have unsubscribed if they open the
message again.
Related keywords: None
Related IMAP capabilities: None
Security considerations: None
Published specification: This document
Jenkins & Eggert Expires 12 June 2025 [Page 9]
Internet-Draft Further IMAP/JMAP keywords & attributes December 2024
Intended usage: COMMON
Scope: BOTH
Owner/Change controller: IESG
4.1.9. $canunsubscribe keyword registration
IMAP/JMAP keyword name: $canunsubscribe
Purpose: Indicate to the client that this message has an
RFC8058-compliant List-Unsubscribe header.
Private or Shared on a server: SHARED
Is it an advisory keyword or may it cause an automatic action: This
keyword is advisory.
When/by whom the keyword is set/cleared: This keyword is set by an
IMAP or JMAP server on messages with an RFC8058-compliant List-
Unsubscribe header. It may only do so if the message passes
vendor-specific reputation checks. It is intended to indicate to
clients that they may be able to do a one-click unsubscribe,
without them having to fetch the List-Unsubscribe header to
determine themself.
Related keywords: None
Related IMAP capabilities: None
Security considerations: None
Published specification: This document
Intended usage: COMMON
Scope: BOTH
Owner/Change controller: IESG
4.1.10. $imported keyword registration
IMAP/JMAP keyword name: $imported
Purpose: Indicate to the client that this message was imported from
another mailbox.
Private or Shared on a server: SHARED
Is it an advisory keyword or may it cause an automatic action: This
keyword is advisory.
When/by whom the keyword is set/cleared: This keyword is set by an
IMAP or JMAP server on messages in imports from another mailbox.
Related keywords: None
Related IMAP capabilities: None
Security considerations: None
Published specification: This document
Intended usage: COMMON
Scope: BOTH
Owner/Change controller: IESG
4.1.11. $istrusted keyword registration
IMAP/JMAP keyword name: $istrusted
Jenkins & Eggert Expires 12 June 2025 [Page 10]
Internet-Draft Further IMAP/JMAP keywords & attributes December 2024
Purpose: Indicate to the client that the authenticity of the from
name and email address have been verified with complete confidence
by the server.
Private or Shared on a server: SHARED
Is it an advisory keyword or may it cause an automatic action: This
keyword is advisory. Clients may show a verification mark (often
a tick icon) on messages with this keyword to indicate their
trusted status to the user.
When/by whom the keyword is set/cleared: This keyword is set by an
IMAP or JMAP server on messages it delivers where it wishes to
confirm to the user that this is a legitimate email they can
trust. It is usually only used for the mailbox provider's own
messages to the customer, where they can know with absolute
certainty that the friendly from name and email address are
legitimate.
Related keywords: None
Related IMAP capabilities: None
Security considerations: Servers should make sure this keyword is
only set for messages that really are trusted!
Published specification: This document
Intended usage: COMMON
Scope: BOTH
Owner/Change controller: IESG
4.1.12. $maskedemail keyword registration
IMAP/JMAP keyword name: $maskedemail
Purpose: Indicate to the client that the message was received via an
alias created for an individual sender.
Private or Shared on a server: SHARED
Is it an advisory keyword or may it cause an automatic action: This
keyword is advisory. Clients may show an icon to indicate to the
user this was received via a masked email address - an alias
created for a specific sender to hide the user's real email
address.
When/by whom the keyword is set/cleared: This keyword is set by an
IMAP or JMAP server on messages it delivers that arrived via such
an alias.
Related keywords: None
Related IMAP capabilities: None
Security considerations: None
Published specification: This document
Intended usage: LIMITED
Scope: BOTH
Owner/Change controller: IESG
Jenkins & Eggert Expires 12 June 2025 [Page 11]
Internet-Draft Further IMAP/JMAP keywords & attributes December 2024
4.1.13. $new keyword registration
IMAP/JMAP keyword name: $new
Purpose: Indicate to the client that a message should be made more
prominent to the user due to a recent action.
Private or Shared on a server: SHARED
Is it an advisory keyword or may it cause an automatic action: This
keyword is advisory. Clients may show the status of the message.
When/by whom the keyword is set/cleared: This keyword is set by an
IMAP or JMAP server on messages after awakening them from snooze.
Clients should clear the keyword when the message is opened.
Related keywords: None
Related IMAP capabilities: None
Security considerations: None
Published specification: This document
Intended usage: LIMITED
Scope: BOTH
Owner/Change controller: IESG
4.1.14. $MailFlagBit0 keyword registration
IMAP/JMAP keyword name: $MailFlagBit0
Purpose: 0 bit part of a 3-bit bitmask that defines the color of the
flag when the has the system flag \Flagged set. See Section 3 for
details.
Private or Shared on a server: SHARED
Is it an advisory keyword or may it cause an automatic action: No
When/by whom the keyword is set/cleared: This keyword is set by an
IMAP or JMAP client as the result of a user action to "flag" a
message for urgent/special attention.
Related keywords: $MailFlagBit1, $MailFlagBit2
Related IMAP capabilities: None
Security considerations: None
Published specification: This document
Intended usage: COMMON
Owner/Change controller: IESG
4.1.15. $MailFlagBit1 keyword registration
IMAP/JMAP keyword name: $MailFlagBit1
Purpose: 0 bit part of a 3-bit bitmask that defines the color of the
flag when the has the system flag \Flagged set. See Section 3 for
details.
Private or Shared on a server: SHARED
Is it an advisory keyword or may it cause an automatic action: No
When/by whom the keyword is set/cleared: This keyword is set by an
IMAP or JMAP client as the result of a user action to "flag" a
message for urgent/special attention.
Jenkins & Eggert Expires 12 June 2025 [Page 12]
Internet-Draft Further IMAP/JMAP keywords & attributes December 2024
Related keywords: $MailFlagBit0, $MailFlagBit2
Related IMAP capabilities: None
Security considerations: None
Published specification: This document
Intended usage: COMMON
Owner/Change controller: IESG
4.1.16. $MailFlagBit2 keyword registration
IMAP/JMAP keyword name: $MailFlagBit2
Purpose: 0 bit part of a 3-bit bitmask that defines the color of the
flag when the has the system flag \Flagged set. See Section 3 for
details.
Private or Shared on a server: SHARED
Is it an advisory keyword or may it cause an automatic action: No
When/by whom the keyword is set/cleared: This keyword is set by an
IMAP or JMAP client as the result of a user action to "flag" a
message for urgent/special attention.
Related keywords: $MailFlagBit0, $MailFlagBit1
Related IMAP capabilities: None
Security considerations: None
Published specification: This document
Intended usage: COMMON
Owner/Change controller: IESG
4.2. IMAP Mailbox Name Attributes Registrations
4.2.1. Snoozed mailbox name attribute registration
Attribute Name: Snoozed
Description: Messages that have been snoozed are moved to this
mailbox until the "awaken" time, when they are moved out of it
again automatically by the server.
Reference: This document.
Usage Notes: Snooze functionality is common among services but not
yet standardised. This attribute marks the mailbox where snoozed
messages may be found, but does not on its own provide a way for
clients to snooze messages.
4.2.2. Scheduled mailbox name attribute registration
Attribute Name: Scheduled
Description: Messages that have been scheduled to send at a later
time. Once the server has sent them at the scheduled time, they
will automatically be deleted or moved from this mailbox by the
server (probably to the \Sent mailbox).
Reference: This document.
Usage Notes: Scheduled sending functionality is common among
Jenkins & Eggert Expires 12 June 2025 [Page 13]
Internet-Draft Further IMAP/JMAP keywords & attributes December 2024
services but not yet standardised. This attribute marks the
mailbox where scheduled messages may be found, but does not on its
own provide a way for clients to schedule messages for sending.
4.2.3. Memos mailbox name attribute registration
Attribute Name: Memos
Description: Messages that have the $memo keyword. Clients creating
memos are recommended to store them in this mailbox. This allows
them to more easily be hidden from the user as "messages", and
presented only as memos instead.
Reference: This document.
Usage Notes: None.
5. Security Considerations
This document should not affect the security of the Internet.
6. References
6.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8457] Leiba, B., Ed., "IMAP "$Important" Keyword and
"\Important" Special-Use Attribute", RFC 8457,
DOI 10.17487/RFC8457, September 2018,
<https://www.rfc-editor.org/info/rfc8457>.
[RFC8474] Gondwana, B., Ed., "IMAP Extension for Object
Identifiers", RFC 8474, DOI 10.17487/RFC8474, September
2018, <https://www.rfc-editor.org/info/rfc8474>.
[RFC8621] Jenkins, N. and C. Newman, "The JSON Meta Application
Protocol (JMAP) for Mail", RFC 8621, DOI 10.17487/RFC8621,
August 2019, <https://www.rfc-editor.org/info/rfc8621>.
[RFC9051] Melnikov, A., Ed. and B. Leiba, Ed., "Internet Message
Access Protocol (IMAP) - Version 4rev2", RFC 9051,
DOI 10.17487/RFC9051, August 2021,
<https://www.rfc-editor.org/info/rfc9051>.
Jenkins & Eggert Expires 12 June 2025 [Page 14]
Internet-Draft Further IMAP/JMAP keywords & attributes December 2024
[RFC5788] Melnikov, A. and D. Cridland, "IMAP4 Keyword Registry",
RFC 5788, DOI 10.17487/RFC5788, March 2010,
<https://www.rfc-editor.org/info/rfc5788>.
Authors' Addresses
Neil Jenkins (editor)
Fastmail
PO Box 234, Collins St West
Melbourne VIC 8007
Australia
Email: neilj@fastmailteam.com
URI: https://www.fastmail.com
Daniel Eggert (editor)
Apple Inc
One Apple Park Way
Cupertino, CA 95014
United States of America
Email: deggert@apple.com
URI: https://www.apple.com
Jenkins & Eggert Expires 12 June 2025 [Page 15]