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spec/draft-ietf-mailmaint-messageflag-mailboxattribute-02.txt
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spec/draft-ietf-mailmaint-messageflag-mailboxattribute-02.txt
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MailMaint N.M. Jenkins, Ed.
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Internet-Draft Fastmail
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Intended status: Informational D. Eggert, Ed.
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Expires: 21 August 2025 Apple Inc
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17 February 2025
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Registration of further IMAP/JMAP keywords and mailbox attribute names
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draft-ietf-mailmaint-messageflag-mailboxattribute-02
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Abstract
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This document defines a number of keywords that have been in use by
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Fastmail and Apple respectively for some time. It defines their
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intended use. Additionally some mailbox names with special meaning
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have been in use by Fastmail, and this document defines their
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intended use. This document registers all of these names with IANA
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to avoid name collisions.
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Status of This Memo
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This Internet-Draft is submitted in full conformance with the
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provisions of BCP 78 and BCP 79.
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Internet-Drafts are working documents of the Internet Engineering
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Task Force (IETF). Note that other groups may also distribute
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working documents as Internet-Drafts. The list of current Internet-
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Drafts is at https://datatracker.ietf.org/drafts/current/.
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Internet-Drafts are draft documents valid for a maximum of six months
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and may be updated, replaced, or obsoleted by other documents at any
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time. It is inappropriate to use Internet-Drafts as reference
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material or to cite them other than as "work in progress."
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This Internet-Draft will expire on 21 August 2025.
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Copyright Notice
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Copyright (c) 2025 IETF Trust and the persons identified as the
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document authors. All rights reserved.
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This document is subject to BCP 78 and the IETF Trust's Legal
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Provisions Relating to IETF Documents (https://trustee.ietf.org/
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license-info) in effect on the date of publication of this document.
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Please review these documents carefully, as they describe your rights
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and restrictions with respect to this document. Code Components
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extracted from this document must include Revised BSD License text as
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described in Section 4.e of the Trust Legal Provisions and are
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provided without warranty as described in the Revised BSD License.
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Table of Contents
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1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
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2. Requirements Language . . . . . . . . . . . . . . . . . . . . 4
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3. Flag Colors . . . . . . . . . . . . . . . . . . . . . . . . . 4
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3.1. Definition of the MailFlagBit Message Keyword . . . . . . 4
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3.2. Implementation Notes . . . . . . . . . . . . . . . . . . 5
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4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 5
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4.1. IMAP/JMAP Keyword Registrations . . . . . . . . . . . . . 5
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4.1.1. $notify keyword registration . . . . . . . . . . . . 5
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4.1.2. $muted keyword registration . . . . . . . . . . . . . 6
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4.1.3. $followed keyword registration . . . . . . . . . . . 7
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4.1.4. $memo keyword registration . . . . . . . . . . . . . 7
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4.1.5. $hasmemo keyword registration . . . . . . . . . . . . 8
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4.1.6. Attachment Detection . . . . . . . . . . . . . . . . 8
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4.1.7. $autosent keyword registration . . . . . . . . . . . 9
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4.1.8. $unsubscribed keyword registration . . . . . . . . . 10
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4.1.9. $canunsubscribe keyword registration . . . . . . . . 10
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4.1.10. $imported keyword registration . . . . . . . . . . . 11
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4.1.11. $istrusted keyword registration . . . . . . . . . . . 11
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4.1.12. $maskedemail keyword registration . . . . . . . . . . 12
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4.1.13. $new keyword registration . . . . . . . . . . . . . . 12
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4.1.14. $MailFlagBit0 keyword registration . . . . . . . . . 13
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4.1.15. $MailFlagBit1 keyword registration . . . . . . . . . 13
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4.1.16. $MailFlagBit2 keyword registration . . . . . . . . . 13
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4.2. IMAP Mailbox Name Attributes Registrations . . . . . . . 14
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4.2.1. Snoozed mailbox name attribute registration . . . . . 14
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4.2.2. Scheduled mailbox name attribute registration . . . . 14
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4.2.3. Memos mailbox name attribute registration . . . . . . 14
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5. Security Considerations . . . . . . . . . . . . . . . . . . . 15
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6. References . . . . . . . . . . . . . . . . . . . . . . . . . 15
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6.1. Normative References . . . . . . . . . . . . . . . . . . 15
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Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 15
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1. Introduction
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The Internet Message Access Protocol (IMAP) specification [RFC9051]
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defines the use of message keywords, and an "IMAP Keywords" registry
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is created in [RFC5788]. Similarly [RFC8457] creates an "IMAP
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Mailbox Name Attributes Registry".
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This document does the following:
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* Defines 16 message keywords
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- $notify
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- $muted
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- $followed
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- $memo
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- $hasmemo
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- $hasattachment
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- $hasnoattachment
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- $autosent
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- $unsubscribed
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- $canunsubscribe
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- $imported
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- $istrusted
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- $maskedemail
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- $new
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- $MailFlagBit0
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- $MailFlagBit1
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- $MailFlagBit2
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* Defines 3 mailbox name attributes
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- Snoozed
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- Scheduled
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- Memos
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* Registers these in the "IMAP Keywords" registry and "IMAP Mailbox
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Name Attributes" registry respectively.
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2. Requirements Language
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The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
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"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
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"OPTIONAL" in this document are to be interpreted as described in BCP
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14 [RFC2119] [RFC8174] when, and only when, they appear in all
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capitals, as shown here.
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3. Flag Colors
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The Internet Message Access Protocol (IMAP) specification [RFC9051]
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defines a \Flagged system flag to mark a message for urgent/special
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attention. The new keywords defined in Sections 4.1.14, 4.1.15, and
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4.1.16 allow such a flagged message to have that flag be of one of 7
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colors.
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3.1. Definition of the MailFlagBit Message Keyword
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The 3 flag color keywords $MailFlagBit0, $MailFlagBit1, and
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$MailFlagBit2 make up a bit pattern that define the color of the flag
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as such:
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+=======+=======+=======+========+
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| Bit 0 | Bit 1 | Bit 2 | Color |
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+=======+=======+=======+========+
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| 0 | 0 | 0 | red |
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+-------+-------+-------+--------+
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| 1 | 0 | 0 | orange |
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+-------+-------+-------+--------+
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| 0 | 1 | 0 | yellow |
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+-------+-------+-------+--------+
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| 1 | 1 | 1 | green |
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+-------+-------+-------+--------+
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| 0 | 0 | 1 | blue |
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+-------+-------+-------+--------+
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| 1 | 0 | 1 | purple |
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+-------+-------+-------+--------+
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| 0 | 1 | 1 | gray |
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+-------+-------+-------+--------+
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Table 1: Flag Colors
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These flags SHOULD be ignored if the \Flagged system flag is not set.
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If the \Flagged system flag is set, the flagged status MAY be
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displayed to the user in the color corresponding to the combination
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of the 3 flag color keywords.
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3.2. Implementation Notes
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A mail client that is aware of these flag color keywords SHOULD clear
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all 3 flag color keywords when the user unflags the message, i.e.
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when unsetting the \Flagged system flag, all 3 flag color keywords
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SHOULD also be unset.
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A mail client SHOULD NOT set any of these flags unless the \Flagged
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system flag is already set or is being set.
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Servers MAY unset these flag color keywords when a client unsets the
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\Flagged system flag.
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4. IANA Considerations
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3 IMAP/JMAP keywords are registered in the IMAP/JMAP keywords
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registry, as established in RFC5788.
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4.1. IMAP/JMAP Keyword Registrations
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4.1.1. $notify keyword registration
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IMAP/JMAP keyword name: $notify
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Purpose: Indicate to the client that a notification should be shown
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for this message.
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Private or Shared on a server: SHARED
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Is it an advisory keyword or may it cause an automatic action: This
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keyword can cause automatic action. On supporting clients, when a
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new message is added to the mailstore with this keyword, the
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client should show the user a notification.
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Mail clients commonly show notifications for new mail, but often
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the only option is to show a notification for every message that
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arrives in the inbox. This keyword allows the user to create
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rules (or the server to automatically determine) specific messages
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that should show a notification.
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Notifications for these messages may be in addition to
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notifications for messages matching other criteria, according to
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user preference set on the client.
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When/by whom the keyword is set/cleared: This keyword is set by a
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server on delivery when a message meets criteria such that the
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user should be shown a notification. It may be cleared by a
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client when the user opens, archives, or otherwise interacts with
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the message. Other clients connected to the same account may
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choose to automatically close the notification if the flag is
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cleared.
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Related keywords: None
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Related IMAP capabilities: None
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Security considerations: None
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Published specification: This document
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Intended usage: COMMON
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Scope: BOTH
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Owner/Change controller: IESG
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4.1.2. $muted keyword registration
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IMAP/JMAP keyword name: $muted
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Purpose: Indicate to the server that the user is not interested in
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future replies to a particular thread.
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Private or Shared on a server: SHARED
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Is it an advisory keyword or may it cause an automatic action: This
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keyword can cause automatic action. On supporting servers, when a
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new message arrives that is in the same thread as a message with
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this keyword the server may automatically process it in some way
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to deprioritise it for the user, for example by moving it to the
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archive or trash, or marking it read. The exact action, whether
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this is customisable by the user, and interaction with user rules
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is vendor specific.
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A message is defined to be in the same thread as another if the
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server assigns them both the same thread id, as defined in
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[RFC8474] Section 5.2 for IMAP or [RFC8621], Section 3 for JMAP.
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When/by whom the keyword is set/cleared: This keyword is set by a
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client when the user indicates they wish to mute or unmute a
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thread. When unmuting a thread, the client must remove the
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keyword from every message in the thread that has it.
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Related keywords: Mutually exclusive with $followed. If both are
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specified on a thread, servers MUST behave as though only
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$followed were set.
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Related IMAP capabilities: None
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Security considerations: Muting a thread can mean a user won't see a
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reply. If someone compromises a user's account, they may mute
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threads where they don't want the user to see the reply, for
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example when sending phishing to the user's contacts. There are
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many other ways an attacker with access to the user's mailbox can
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also achieve this however, so this is not greatly increasing the
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attack surface.
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Published specification: This document
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Intended usage: COMMON
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Scope: BOTH
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Owner/Change controller: IESG
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4.1.3. $followed keyword registration
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IMAP/JMAP keyword name: $followed
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Purpose: Indicate to the server that the user is particularly
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interested in future replies to a particular thread.
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Private or Shared on a server: SHARED
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Is it an advisory keyword or may it cause an automatic action: This
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keyword can cause automatic action. On supporting servers, when a
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new message arrives that is in the same thread as a message with
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this keyword the server may automatically process it in some way
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to prioritise it for the user, for example by ignoring rules that
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would make it skip the inbox, or automatically adding the $notify
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keyword. The exact action, whether this is customisable by the
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user, and interaction with user rules is vendor specific.
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A message is defined to be in the same thread as another if the
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server assigns them both the same thread id, as defined in
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[RFC8474] Section 5.2 for IMAP or [RFC8621], Section 3 for JMAP.
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When/by whom the keyword is set/cleared: This keyword is set by a
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client when the user indicates they wish to follow or unfollow a
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thread. When unfollowing a thread, the client must remove the
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keyword from every message in the thread that has it.
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Related keywords: Mutually exclusive with $muted. If both are
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specified on a thread, servers MUST behave as though only
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$followed were set.
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Related IMAP capabilities: None
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Security considerations: None
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Published specification: This document
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Intended usage: COMMON
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Scope: BOTH
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Owner/Change controller: IESG
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4.1.4. $memo keyword registration
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IMAP/JMAP keyword name: $memo
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Purpose: Indicate to the client that a message is a note-to-self
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from the user regarding another message in the same thread.
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Private or Shared on a server: SHARED
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Is it an advisory keyword or may it cause an automatic action: This
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keyword is advisory.
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When/by whom the keyword is set/cleared: This keyword is set by a
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client when creating such a message. The message should otherwise
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be contructed like a reply to the message to which this memo is
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attached (i.e. appropriate Subject and Reply-To headers set). In
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supporting clients, messages with this flag may be presented
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differently to the user, attached to the message the memo is
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commenting on, and may offer the user the ability to edit or
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delete the memo. (As messages are immutable, editing requires
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replacing the message.)
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Related keywords: The $hasmemo keyword should be set/cleared at the
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same time.
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Related IMAP capabilities: None
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Security considerations: None
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Published specification: This document
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Intended usage: COMMON
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Scope: BOTH
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Owner/Change controller: IESG
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+
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4.1.5. $hasmemo keyword registration
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+
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IMAP/JMAP keyword name: $hasmemo
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Purpose: Indicate to the client that a message has an associated
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memo with the $memo keyword.
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Private or Shared on a server: SHARED
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Is it an advisory keyword or may it cause an automatic action: This
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keyword is advisory.
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When/by whom the keyword is set/cleared: This keyword is set by a
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client when creating a memo. The memo gets the $memo keyword, the
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+
message it is a note for gets the $hasmemo keyword. This keyword
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can help in searching for messages with memos, or deciding whether
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+
to fetch the whole thread to look for memos when loading a
422
+
mailbox.
423
+
Related keywords: A message with the $memo keyword should be
424
+
created/destroyed at the same time.
425
+
Related IMAP capabilities: None
426
+
Security considerations: None
427
+
Published specification: This document
428
+
Intended usage: COMMON
429
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Scope: BOTH
430
+
Owner/Change controller: IESG
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+
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+
4.1.6. Attachment Detection
433
+
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The $hasattachment and $hasnoattachment are mutually exclusive. A
435
+
message SHOULD NOT contain both keywords.
436
+
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+
4.1.6.1. $hasattachment keyword registration
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+
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+
IMAP/JMAP keyword name: $hasattachment
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Purpose: Indicate to the client that a message has an attachment.
441
+
Private or Shared on a server: SHARED
442
+
Is it an advisory keyword or may it cause an automatic action: This
443
+
keyword is advisory.
444
+
When/by whom the keyword is set/cleared: This keyword is set by a
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+
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+
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+
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server on messages it determines have an attachment. This can
454
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help mailbox clients indicate this to the user without having to
455
+
fetch the full message body structure. Over JMAP, the
456
+
"hasAttachment" Email property should indicate the same value.
457
+
Related keywords: $hasnoattachment
458
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Related IMAP capabilities: None
459
+
Security considerations: None
460
+
Published specification: This document
461
+
Intended usage: COMMON
462
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Scope: BOTH
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Owner/Change controller: IESG
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+
4.1.6.2. $hasnoattachment keyword registration
466
+
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+
IMAP/JMAP keyword name: $hasnoattachment
468
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Purpose: Indicate to the client that a message does not have an
469
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attachment.
470
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Private or Shared on a server: SHARED
471
+
Is it an advisory keyword or may it cause an automatic action: This
472
+
keyword is advisory.
473
+
When/by whom the keyword is set/cleared: This keyword is set by a
474
+
server on messages it determines does NOT have an attachment.
475
+
Over JMAP, the "hasNoAttachment" Email property should indicate
476
+
the same value. This keyword is needed in addition to the
477
+
$hasattachment keyword, as a client cannot otherwise determine
478
+
whether the server has processed the message for the presence of
479
+
an attachment. In other words, the absence of the $hasattachment
480
+
keyword for a message does not tell a client whether the message
481
+
actually contains an attachment, as the client has no information
482
+
on whether the server has processed the message.
483
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Related keywords: None
484
+
Related IMAP capabilities: None
485
+
Security considerations: None
486
+
Published specification: This document
487
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Intended usage: COMMON
488
+
Scope: BOTH
489
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Owner/Change controller: IESG
490
+
491
+
4.1.7. $autosent keyword registration
492
+
493
+
IMAP/JMAP keyword name: $autosent
494
+
Purpose: Indicate to the client that a message was sent
495
+
automatically as a response due to a user rule or setting.
496
+
Private or Shared on a server: SHARED
497
+
Is it an advisory keyword or may it cause an automatic action: This
498
+
keyword is advisory.
499
+
When/by whom the keyword is set/cleared: This keyword is set by a
500
+
501
+
502
+
503
+
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server on the user's copy of their vacation response and other
510
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automated messages sent on behalf of the user. Clients may use
511
+
this to indicate to the user that this message was sent
512
+
automatically, as if they have forgotten the rule or vacation
513
+
response is set up they may be surprised to see it among their
514
+
sent items.
515
+
Related keywords: None
516
+
Related IMAP capabilities: None
517
+
Security considerations: None
518
+
Published specification: This document
519
+
Intended usage: COMMON
520
+
Scope: BOTH
521
+
Owner/Change controller: IESG
522
+
523
+
4.1.8. $unsubscribed keyword registration
524
+
525
+
IMAP/JMAP keyword name: $unsubscribed
526
+
Purpose: Indicate to the client that it has unsubscribed from the
527
+
thread this message is on.
528
+
Private or Shared on a server: SHARED
529
+
Is it an advisory keyword or may it cause an automatic action: This
530
+
keyword is advisory.
531
+
When/by whom the keyword is set/cleared: This keyword is set by a
532
+
client on a message after attempting to unsubscribe from the
533
+
mailing list this message came from (e.g., after attempting
534
+
RFC8058 one-click List-Unsubscribe). It allows clients to remind
535
+
the user that they have unsubscribed if they open the message
536
+
again.
537
+
Related keywords: None
538
+
Related IMAP capabilities: None
539
+
Security considerations: None
540
+
Published specification: This document
541
+
Intended usage: COMMON
542
+
Scope: BOTH
543
+
Owner/Change controller: IESG
544
+
545
+
4.1.9. $canunsubscribe keyword registration
546
+
547
+
IMAP/JMAP keyword name: $canunsubscribe
548
+
Purpose: Indicate to the client that this message has an
549
+
RFC8058-compliant List-Unsubscribe header.
550
+
Private or Shared on a server: SHARED
551
+
Is it an advisory keyword or may it cause an automatic action: This
552
+
keyword is advisory.
553
+
When/by whom the keyword is set/cleared: This keyword is set by a
554
+
555
+
556
+
557
+
558
+
559
+
560
+
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+
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+
565
+
server on messages with an RFC8058-compliant List-Unsubscribe
566
+
header. It may only do so if the message passes vendor-specific
567
+
reputation checks. It is intended to indicate to clients that
568
+
they may be able to do a one-click unsubscribe, without them
569
+
having to fetch the List-Unsubscribe header to determine themself.
570
+
Related keywords: None
571
+
Related IMAP capabilities: None
572
+
Security considerations: None
573
+
Published specification: This document
574
+
Intended usage: COMMON
575
+
Scope: BOTH
576
+
Owner/Change controller: IESG
577
+
578
+
4.1.10. $imported keyword registration
579
+
580
+
IMAP/JMAP keyword name: $imported
581
+
Purpose: Indicate to the client that this message was imported from
582
+
another mailbox.
583
+
Private or Shared on a server: SHARED
584
+
Is it an advisory keyword or may it cause an automatic action: This
585
+
keyword is advisory.
586
+
When/by whom the keyword is set/cleared: This keyword is set by a
587
+
server on messages in imports from another mailbox.
588
+
Related keywords: None
589
+
Related IMAP capabilities: None
590
+
Security considerations: None
591
+
Published specification: This document
592
+
Intended usage: COMMON
593
+
Scope: BOTH
594
+
Owner/Change controller: IESG
595
+
596
+
4.1.11. $istrusted keyword registration
597
+
598
+
IMAP/JMAP keyword name: $istrusted
599
+
Purpose: Indicate to the client that the authenticity of the from
600
+
name and email address have been verified with complete confidence
601
+
by the server.
602
+
Private or Shared on a server: SHARED
603
+
Is it an advisory keyword or may it cause an automatic action: This
604
+
keyword is advisory. Clients may show a verification mark (often
605
+
a tick icon) on messages with this keyword to indicate their
606
+
trusted status to the user.
607
+
When/by whom the keyword is set/cleared: This keyword is set by a
608
+
server on messages it delivers where it wishes to confirm to the
609
+
user that this is a legitimate email they can trust. It is
610
+
usually only used for the mailbox provider's own messages to the
611
+
customer, where they can know with absolute certainty that the
612
+
friendly from name and email address are legitimate.
613
+
614
+
615
+
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+
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+
620
+
621
+
Related keywords: None
622
+
Related IMAP capabilities: None
623
+
Security considerations: Servers should make sure this keyword is
624
+
only set for messages that really are trusted!
625
+
Published specification: This document
626
+
Intended usage: COMMON
627
+
Scope: BOTH
628
+
Owner/Change controller: IESG
629
+
630
+
4.1.12. $maskedemail keyword registration
631
+
632
+
IMAP/JMAP keyword name: $maskedemail
633
+
Purpose: Indicate to the client that the message was received via an
634
+
alias created for an individual sender.
635
+
Private or Shared on a server: SHARED
636
+
Is it an advisory keyword or may it cause an automatic action: This
637
+
keyword is advisory. Clients may show an icon to indicate to the
638
+
user this was received via a masked email address - an alias
639
+
created for a specific sender to hide the user's real email
640
+
address.
641
+
When/by whom the keyword is set/cleared: This keyword is set by a
642
+
server on messages it delivers that arrived via such an alias.
643
+
Related keywords: None
644
+
Related IMAP capabilities: None
645
+
Security considerations: None
646
+
Published specification: This document
647
+
Intended usage: LIMITED
648
+
Scope: BOTH
649
+
Owner/Change controller: IESG
650
+
651
+
4.1.13. $new keyword registration
652
+
653
+
IMAP/JMAP keyword name: $new
654
+
Purpose: Indicate to the client that a message should be made more
655
+
prominent to the user due to a recent action.
656
+
Private or Shared on a server: SHARED
657
+
Is it an advisory keyword or may it cause an automatic action: This
658
+
keyword is advisory. Clients may show the status of the message.
659
+
When/by whom the keyword is set/cleared: This keyword is set by a
660
+
server on messages after awakening them from snooze. Clients
661
+
should clear the keyword when the message is opened.
662
+
Related keywords: None
663
+
Related IMAP capabilities: None
664
+
Security considerations: None
665
+
Published specification: This document
666
+
Intended usage: LIMITED
667
+
Scope: BOTH
668
+
Owner/Change controller: IESG
669
+
670
+
671
+
672
+
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+
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+
677
+
4.1.14. $MailFlagBit0 keyword registration
678
+
679
+
IMAP/JMAP keyword name: $MailFlagBit0
680
+
Purpose: 0 bit part of a 3-bit bitmask that defines the color of the
681
+
flag when the has the system flag \Flagged set. See Section 3 for
682
+
details.
683
+
Private or Shared on a server: SHARED
684
+
Is it an advisory keyword or may it cause an automatic action: No
685
+
When/by whom the keyword is set/cleared: This keyword is set by a
686
+
client as the result of a user action to "flag" a message for
687
+
urgent/special attention.
688
+
Related keywords: $MailFlagBit1, $MailFlagBit2
689
+
Related IMAP capabilities: None
690
+
Security considerations: None
691
+
Published specification: This document
692
+
Intended usage: COMMON
693
+
Owner/Change controller: IESG
694
+
695
+
4.1.15. $MailFlagBit1 keyword registration
696
+
697
+
IMAP/JMAP keyword name: $MailFlagBit1
698
+
Purpose: 0 bit part of a 3-bit bitmask that defines the color of the
699
+
flag when the has the system flag \Flagged set. See Section 3 for
700
+
details.
701
+
Private or Shared on a server: SHARED
702
+
Is it an advisory keyword or may it cause an automatic action: No
703
+
When/by whom the keyword is set/cleared: This keyword is set by a
704
+
client as the result of a user action to "flag" a message for
705
+
urgent/special attention.
706
+
Related keywords: $MailFlagBit0, $MailFlagBit2
707
+
Related IMAP capabilities: None
708
+
Security considerations: None
709
+
Published specification: This document
710
+
Intended usage: COMMON
711
+
Owner/Change controller: IESG
712
+
713
+
4.1.16. $MailFlagBit2 keyword registration
714
+
715
+
IMAP/JMAP keyword name: $MailFlagBit2
716
+
Purpose: 0 bit part of a 3-bit bitmask that defines the color of the
717
+
flag when the has the system flag \Flagged set. See Section 3 for
718
+
details.
719
+
Private or Shared on a server: SHARED
720
+
Is it an advisory keyword or may it cause an automatic action: No
721
+
When/by whom the keyword is set/cleared: This keyword is set by a
722
+
client as the result of a user action to "flag" a message for
723
+
urgent/special attention.
724
+
Related keywords: $MailFlagBit0, $MailFlagBit1
725
+
726
+
727
+
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+
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+
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+
732
+
733
+
Related IMAP capabilities: None
734
+
Security considerations: None
735
+
Published specification: This document
736
+
Intended usage: COMMON
737
+
Owner/Change controller: IESG
738
+
739
+
4.2. IMAP Mailbox Name Attributes Registrations
740
+
741
+
This section lists mailbox name attributes to be registered with the
742
+
"IMAP Mailbox Name Attributes" created with [RFC8457].
743
+
744
+
Note that none of the attribute names in this seciton have an implied
745
+
backslash. This sets them apart from those specified in Section 2 of
746
+
[RFC6154].
747
+
748
+
4.2.1. Snoozed mailbox name attribute registration
749
+
750
+
Attribute Name: Snoozed
751
+
Description: Messages that have been snoozed are moved to this
752
+
mailbox until the "awaken" time, when they are moved out of it
753
+
again automatically by the server.
754
+
Reference: This document.
755
+
Usage Notes: Snooze functionality is common among services but not
756
+
yet standardised. This attribute marks the mailbox where snoozed
757
+
messages may be found, but does not on its own provide a way for
758
+
clients to snooze messages.
759
+
760
+
4.2.2. Scheduled mailbox name attribute registration
761
+
762
+
Attribute Name: Scheduled
763
+
Description: Messages that have been scheduled to send at a later
764
+
time. Once the server has sent them at the scheduled time, they
765
+
will automatically be deleted or moved from this mailbox by the
766
+
server (probably to the \Sent mailbox).
767
+
Reference: This document.
768
+
Usage Notes: Scheduled sending functionality is common among
769
+
services but not yet standardised. This attribute marks the
770
+
mailbox where scheduled messages may be found, but does not on its
771
+
own provide a way for clients to schedule messages for sending.
772
+
773
+
4.2.3. Memos mailbox name attribute registration
774
+
775
+
Attribute Name: Memos
776
+
Description: Messages that have the $memo keyword. Clients creating
777
+
memos are recommended to store them in this mailbox. This allows
778
+
them to more easily be hidden from the user as "messages", and
779
+
presented only as memos instead.
780
+
Reference: This document.
781
+
782
+
783
+
784
+
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+
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+
788
+
789
+
Usage Notes: None.
790
+
791
+
5. Security Considerations
792
+
793
+
This document should not affect the security of the Internet.
794
+
795
+
6. References
796
+
797
+
6.1. Normative References
798
+
799
+
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
800
+
Requirement Levels", BCP 14, RFC 2119,
801
+
DOI 10.17487/RFC2119, March 1997,
802
+
<https://www.rfc-editor.org/info/rfc2119>.
803
+
804
+
[RFC6154] Leiba, B. and J. Nicolson, "IMAP LIST Extension for
805
+
Special-Use Mailboxes", RFC 6154, DOI 10.17487/RFC6154,
806
+
March 2011, <https://www.rfc-editor.org/info/rfc6154>.
807
+
808
+
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
809
+
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
810
+
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
811
+
812
+
[RFC8457] Leiba, B., Ed., "IMAP "$Important" Keyword and
813
+
"\Important" Special-Use Attribute", RFC 8457,
814
+
DOI 10.17487/RFC8457, September 2018,
815
+
<https://www.rfc-editor.org/info/rfc8457>.
816
+
817
+
[RFC8474] Gondwana, B., Ed., "IMAP Extension for Object
818
+
Identifiers", RFC 8474, DOI 10.17487/RFC8474, September
819
+
2018, <https://www.rfc-editor.org/info/rfc8474>.
820
+
821
+
[RFC8621] Jenkins, N. and C. Newman, "The JSON Meta Application
822
+
Protocol (JMAP) for Mail", RFC 8621, DOI 10.17487/RFC8621,
823
+
August 2019, <https://www.rfc-editor.org/info/rfc8621>.
824
+
825
+
[RFC9051] Melnikov, A., Ed. and B. Leiba, Ed., "Internet Message
826
+
Access Protocol (IMAP) - Version 4rev2", RFC 9051,
827
+
DOI 10.17487/RFC9051, August 2021,
828
+
<https://www.rfc-editor.org/info/rfc9051>.
829
+
830
+
[RFC5788] Melnikov, A. and D. Cridland, "IMAP4 Keyword Registry",
831
+
RFC 5788, DOI 10.17487/RFC5788, March 2010,
832
+
<https://www.rfc-editor.org/info/rfc5788>.
833
+
834
+
Authors' Addresses
835
+
836
+
837
+
838
+
839
+
840
+
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+
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+
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843
+
844
+
845
+
Neil Jenkins (editor)
846
+
Fastmail
847
+
PO Box 234, Collins St West
848
+
Melbourne VIC 8007
849
+
Australia
850
+
Email: neilj@fastmailteam.com
851
+
URI: https://www.fastmail.com
852
+
853
+
854
+
Daniel Eggert (editor)
855
+
Apple Inc
856
+
One Apple Park Way
857
+
Cupertino, CA 95014
858
+
United States of America
859
+
Email: deggert@apple.com
860
+
URI: https://www.apple.com
861
+
862
+
863
+
864
+
865
+
866
+
867
+
868
+
869
+
870
+
871
+
872
+
873
+
874
+
875
+
876
+
877
+
878
+
879
+
880
+
881
+
882
+
883
+
884
+
885
+
886
+
887
+
888
+
889
+
890
+
891
+
892
+
893
+
894
+
895
+
896
+
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