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Version: 0.16

IMAP and POP3

IMAP protocol settings cover request handling, authentication, timeouts, and rate limits. Several of these settings also apply to the POP3 server, as both protocols share the same configuration surface. IMAP and POP3 settings are carried on the Imap singleton (found in the WebUI under Settings › Network › IMAP). Default special-use folders, which are used by IMAP clients as well as JMAP, are configured on the Email singleton (found in the WebUI under Settings › Email › Defaults, Settings › Email › Encryption, Settings › Email › Limits, Settings › Email › Storage).

Request size​

The maxRequestSize field sets the maximum size of an IMAP request that the server will accept. Requests larger than this limit are rejected. The default is "50mb".

Authentication​

Two fields on the Imap singleton control IMAP and POP3 authentication behaviour:

  • maxAuthFailures: maximum number of authentication attempts allowed before the session is disconnected. Default 3.
  • allowPlainTextAuth: whether plain-text authentication is permitted over an unencrypted connection. For security reasons, this should be left at its default false unless strictly required, so that credentials are not transmitted in the clear.

Example:

{
  "maxAuthFailures": 3,
  "allowPlainTextAuth": false
}

Default folders​

Default special-use folders created for new accounts are defined by defaultFolders on the Email singleton. The field is a map keyed by special-use type; supported keys are inbox, trash, junk, drafts, archive, sent, shared, important, memos, scheduled, and snoozed.

Each entry carries the fields of the nested EmailFolder type:

  • name: display name of the folder. Required.
  • create: whether the folder is created automatically. Default true.
  • subscribe: whether the folder is subscribed by default. Default true.
  • aliases: additional names under which the folder is recognised.

Example:

{
  "defaultFolders": {
    "sent": {"name": "Sent Items", "create": true, "subscribe": true},
    "junk": {"name": "SPAM", "create": true, "subscribe": false},
    "shared": {"name": "Shared Folders"}
  }
}

Timeouts​

Idle timeouts are controlled by three fields on the Imap singleton:

  • timeoutAuthenticated: time an authenticated session can remain idle before the server terminates it. Default "30m".
  • timeoutAnonymous: time an anonymous (unauthenticated) session can stay inactive before being ended by the server. Default "1m".
  • timeoutIdle: time a connection can stay idle in the IMAP IDLE state before the server breaks the connection. Default "30m".

Example:

{
  "timeoutAuthenticated": "30m",
  "timeoutAnonymous": "1m",
  "timeoutIdle": "30m"
}