diff --git a/webmail/api.go b/webmail/api.go
index 21e490d..fc9b7e3 100644
--- a/webmail/api.go
+++ b/webmail/api.go
@@ -497,22 +497,23 @@ type Attachment struct {
 // Addresses are formatted as just email address, or with a name like "name
 // <user@host>".
 type SubmitMessage struct {
-	From               string
-	To                 []string
-	Cc                 []string
-	Bcc                []string
-	ReplyTo            string // If non-empty, Reply-To header to add to message.
-	Subject            string
-	TextBody           string
-	Attachments        []File
-	ForwardAttachments ForwardAttachments
-	IsForward          bool
-	ResponseMessageID  int64      // If set, this was a reply or forward, based on IsForward.
-	UserAgent          string     // User-Agent header added if not empty.
-	RequireTLS         *bool      // For "Require TLS" extension during delivery.
-	FutureRelease      *time.Time // If set, time (in the future) when message should be delivered from queue.
-	ArchiveThread      bool       // If set, thread is archived after sending message.
-	DraftMessageID     int64      // If set, draft message that will be removed after sending.
+	From                      string
+	To                        []string
+	Cc                        []string
+	Bcc                       []string
+	ReplyTo                   string // If non-empty, Reply-To header to add to message.
+	Subject                   string
+	TextBody                  string
+	Attachments               []File
+	ForwardAttachments        ForwardAttachments
+	IsForward                 bool
+	ResponseMessageID         int64      // If set, this was a reply or forward, based on IsForward.
+	UserAgent                 string     // User-Agent header added if not empty.
+	RequireTLS                *bool      // For "Require TLS" extension during delivery.
+	FutureRelease             *time.Time // If set, time (in the future) when message should be delivered from queue.
+	ArchiveThread             bool       // If set, thread is archived after sending message.
+	ArchiveReferenceMailboxID int64      // If ArchiveThread is set, thread messages from this mailbox ID are moved to the archive mailbox ID. E.g. of Inbox.
+	DraftMessageID            int64      // If set, draft message that will be removed after sending.
 }
 
 // ForwardAttachments references attachments by a list of message.Part paths.
@@ -1057,7 +1058,7 @@ func (w Webmail) MessageSubmit(ctx context.Context, m SubmitMessage) {
 
 					var msgIDs []int64
 					q := bstore.QueryTx[store.Message](tx)
-					q.FilterNonzero(store.Message{ThreadID: rm.ThreadID, MailboxID: rm.MailboxID})
+					q.FilterNonzero(store.Message{ThreadID: rm.ThreadID, MailboxID: m.ArchiveReferenceMailboxID})
 					q.FilterEqual("Expunged", false)
 					err = q.IDs(&msgIDs)
 					xcheckf(ctx, err, "listing messages in thread to archive")
diff --git a/webmail/api.json b/webmail/api.json
index 148c54c..2d6c4e2 100644
--- a/webmail/api.json
+++ b/webmail/api.json
@@ -1501,6 +1501,13 @@
 						"bool"
 					]
 				},
+				{
+					"Name": "ArchiveReferenceMailboxID",
+					"Docs": "If ArchiveThread is set, thread messages from this mailbox ID are moved to the archive mailbox ID. E.g. of Inbox.",
+					"Typewords": [
+						"int64"
+					]
+				},
 				{
 					"Name": "DraftMessageID",
 					"Docs": "If set, draft message that will be removed after sending.",
diff --git a/webmail/api.ts b/webmail/api.ts
index 0b637da..f7941d4 100644
--- a/webmail/api.ts
+++ b/webmail/api.ts
@@ -166,6 +166,7 @@ export interface SubmitMessage {
 	RequireTLS?: boolean | null  // For "Require TLS" extension during delivery.
 	FutureRelease?: Date | null  // If set, time (in the future) when message should be delivered from queue.
 	ArchiveThread: boolean  // If set, thread is archived after sending message.
+	ArchiveReferenceMailboxID: number  // If ArchiveThread is set, thread messages from this mailbox ID are moved to the archive mailbox ID. E.g. of Inbox.
 	DraftMessageID: number  // If set, draft message that will be removed after sending.
 }
 
@@ -598,7 +599,7 @@ export const types: TypenameMap = {
 	"Domain": {"Name":"Domain","Docs":"","Fields":[{"Name":"ASCII","Docs":"","Typewords":["string"]},{"Name":"Unicode","Docs":"","Typewords":["string"]}]},
 	"FromAddressSettings": {"Name":"FromAddressSettings","Docs":"","Fields":[{"Name":"FromAddress","Docs":"","Typewords":["string"]},{"Name":"ViewMode","Docs":"","Typewords":["ViewMode"]}]},
 	"ComposeMessage": {"Name":"ComposeMessage","Docs":"","Fields":[{"Name":"From","Docs":"","Typewords":["string"]},{"Name":"To","Docs":"","Typewords":["[]","string"]},{"Name":"Cc","Docs":"","Typewords":["[]","string"]},{"Name":"Bcc","Docs":"","Typewords":["[]","string"]},{"Name":"ReplyTo","Docs":"","Typewords":["string"]},{"Name":"Subject","Docs":"","Typewords":["string"]},{"Name":"TextBody","Docs":"","Typewords":["string"]},{"Name":"ResponseMessageID","Docs":"","Typewords":["int64"]},{"Name":"DraftMessageID","Docs":"","Typewords":["int64"]}]},
-	"SubmitMessage": {"Name":"SubmitMessage","Docs":"","Fields":[{"Name":"From","Docs":"","Typewords":["string"]},{"Name":"To","Docs":"","Typewords":["[]","string"]},{"Name":"Cc","Docs":"","Typewords":["[]","string"]},{"Name":"Bcc","Docs":"","Typewords":["[]","string"]},{"Name":"ReplyTo","Docs":"","Typewords":["string"]},{"Name":"Subject","Docs":"","Typewords":["string"]},{"Name":"TextBody","Docs":"","Typewords":["string"]},{"Name":"Attachments","Docs":"","Typewords":["[]","File"]},{"Name":"ForwardAttachments","Docs":"","Typewords":["ForwardAttachments"]},{"Name":"IsForward","Docs":"","Typewords":["bool"]},{"Name":"ResponseMessageID","Docs":"","Typewords":["int64"]},{"Name":"UserAgent","Docs":"","Typewords":["string"]},{"Name":"RequireTLS","Docs":"","Typewords":["nullable","bool"]},{"Name":"FutureRelease","Docs":"","Typewords":["nullable","timestamp"]},{"Name":"ArchiveThread","Docs":"","Typewords":["bool"]},{"Name":"DraftMessageID","Docs":"","Typewords":["int64"]}]},
+	"SubmitMessage": {"Name":"SubmitMessage","Docs":"","Fields":[{"Name":"From","Docs":"","Typewords":["string"]},{"Name":"To","Docs":"","Typewords":["[]","string"]},{"Name":"Cc","Docs":"","Typewords":["[]","string"]},{"Name":"Bcc","Docs":"","Typewords":["[]","string"]},{"Name":"ReplyTo","Docs":"","Typewords":["string"]},{"Name":"Subject","Docs":"","Typewords":["string"]},{"Name":"TextBody","Docs":"","Typewords":["string"]},{"Name":"Attachments","Docs":"","Typewords":["[]","File"]},{"Name":"ForwardAttachments","Docs":"","Typewords":["ForwardAttachments"]},{"Name":"IsForward","Docs":"","Typewords":["bool"]},{"Name":"ResponseMessageID","Docs":"","Typewords":["int64"]},{"Name":"UserAgent","Docs":"","Typewords":["string"]},{"Name":"RequireTLS","Docs":"","Typewords":["nullable","bool"]},{"Name":"FutureRelease","Docs":"","Typewords":["nullable","timestamp"]},{"Name":"ArchiveThread","Docs":"","Typewords":["bool"]},{"Name":"ArchiveReferenceMailboxID","Docs":"","Typewords":["int64"]},{"Name":"DraftMessageID","Docs":"","Typewords":["int64"]}]},
 	"File": {"Name":"File","Docs":"","Fields":[{"Name":"Filename","Docs":"","Typewords":["string"]},{"Name":"DataURI","Docs":"","Typewords":["string"]}]},
 	"ForwardAttachments": {"Name":"ForwardAttachments","Docs":"","Fields":[{"Name":"MessageID","Docs":"","Typewords":["int64"]},{"Name":"Paths","Docs":"","Typewords":["[]","[]","int32"]}]},
 	"Mailbox": {"Name":"Mailbox","Docs":"","Fields":[{"Name":"ID","Docs":"","Typewords":["int64"]},{"Name":"Name","Docs":"","Typewords":["string"]},{"Name":"UIDValidity","Docs":"","Typewords":["uint32"]},{"Name":"UIDNext","Docs":"","Typewords":["UID"]},{"Name":"Archive","Docs":"","Typewords":["bool"]},{"Name":"Draft","Docs":"","Typewords":["bool"]},{"Name":"Junk","Docs":"","Typewords":["bool"]},{"Name":"Sent","Docs":"","Typewords":["bool"]},{"Name":"Trash","Docs":"","Typewords":["bool"]},{"Name":"Keywords","Docs":"","Typewords":["[]","string"]},{"Name":"HaveCounts","Docs":"","Typewords":["bool"]},{"Name":"Total","Docs":"","Typewords":["int64"]},{"Name":"Deleted","Docs":"","Typewords":["int64"]},{"Name":"Unread","Docs":"","Typewords":["int64"]},{"Name":"Unseen","Docs":"","Typewords":["int64"]},{"Name":"Size","Docs":"","Typewords":["int64"]}]},
diff --git a/webmail/msg.js b/webmail/msg.js
index f0e03e6..f93eea6 100644
--- a/webmail/msg.js
+++ b/webmail/msg.js
@@ -306,7 +306,7 @@ var api;
 		"Domain": { "Name": "Domain", "Docs": "", "Fields": [{ "Name": "ASCII", "Docs": "", "Typewords": ["string"] }, { "Name": "Unicode", "Docs": "", "Typewords": ["string"] }] },
 		"FromAddressSettings": { "Name": "FromAddressSettings", "Docs": "", "Fields": [{ "Name": "FromAddress", "Docs": "", "Typewords": ["string"] }, { "Name": "ViewMode", "Docs": "", "Typewords": ["ViewMode"] }] },
 		"ComposeMessage": { "Name": "ComposeMessage", "Docs": "", "Fields": [{ "Name": "From", "Docs": "", "Typewords": ["string"] }, { "Name": "To", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "Cc", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "Bcc", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "ReplyTo", "Docs": "", "Typewords": ["string"] }, { "Name": "Subject", "Docs": "", "Typewords": ["string"] }, { "Name": "TextBody", "Docs": "", "Typewords": ["string"] }, { "Name": "ResponseMessageID", "Docs": "", "Typewords": ["int64"] }, { "Name": "DraftMessageID", "Docs": "", "Typewords": ["int64"] }] },
-		"SubmitMessage": { "Name": "SubmitMessage", "Docs": "", "Fields": [{ "Name": "From", "Docs": "", "Typewords": ["string"] }, { "Name": "To", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "Cc", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "Bcc", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "ReplyTo", "Docs": "", "Typewords": ["string"] }, { "Name": "Subject", "Docs": "", "Typewords": ["string"] }, { "Name": "TextBody", "Docs": "", "Typewords": ["string"] }, { "Name": "Attachments", "Docs": "", "Typewords": ["[]", "File"] }, { "Name": "ForwardAttachments", "Docs": "", "Typewords": ["ForwardAttachments"] }, { "Name": "IsForward", "Docs": "", "Typewords": ["bool"] }, { "Name": "ResponseMessageID", "Docs": "", "Typewords": ["int64"] }, { "Name": "UserAgent", "Docs": "", "Typewords": ["string"] }, { "Name": "RequireTLS", "Docs": "", "Typewords": ["nullable", "bool"] }, { "Name": "FutureRelease", "Docs": "", "Typewords": ["nullable", "timestamp"] }, { "Name": "ArchiveThread", "Docs": "", "Typewords": ["bool"] }, { "Name": "DraftMessageID", "Docs": "", "Typewords": ["int64"] }] },
+		"SubmitMessage": { "Name": "SubmitMessage", "Docs": "", "Fields": [{ "Name": "From", "Docs": "", "Typewords": ["string"] }, { "Name": "To", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "Cc", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "Bcc", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "ReplyTo", "Docs": "", "Typewords": ["string"] }, { "Name": "Subject", "Docs": "", "Typewords": ["string"] }, { "Name": "TextBody", "Docs": "", "Typewords": ["string"] }, { "Name": "Attachments", "Docs": "", "Typewords": ["[]", "File"] }, { "Name": "ForwardAttachments", "Docs": "", "Typewords": ["ForwardAttachments"] }, { "Name": "IsForward", "Docs": "", "Typewords": ["bool"] }, { "Name": "ResponseMessageID", "Docs": "", "Typewords": ["int64"] }, { "Name": "UserAgent", "Docs": "", "Typewords": ["string"] }, { "Name": "RequireTLS", "Docs": "", "Typewords": ["nullable", "bool"] }, { "Name": "FutureRelease", "Docs": "", "Typewords": ["nullable", "timestamp"] }, { "Name": "ArchiveThread", "Docs": "", "Typewords": ["bool"] }, { "Name": "ArchiveReferenceMailboxID", "Docs": "", "Typewords": ["int64"] }, { "Name": "DraftMessageID", "Docs": "", "Typewords": ["int64"] }] },
 		"File": { "Name": "File", "Docs": "", "Fields": [{ "Name": "Filename", "Docs": "", "Typewords": ["string"] }, { "Name": "DataURI", "Docs": "", "Typewords": ["string"] }] },
 		"ForwardAttachments": { "Name": "ForwardAttachments", "Docs": "", "Fields": [{ "Name": "MessageID", "Docs": "", "Typewords": ["int64"] }, { "Name": "Paths", "Docs": "", "Typewords": ["[]", "[]", "int32"] }] },
 		"Mailbox": { "Name": "Mailbox", "Docs": "", "Fields": [{ "Name": "ID", "Docs": "", "Typewords": ["int64"] }, { "Name": "Name", "Docs": "", "Typewords": ["string"] }, { "Name": "UIDValidity", "Docs": "", "Typewords": ["uint32"] }, { "Name": "UIDNext", "Docs": "", "Typewords": ["UID"] }, { "Name": "Archive", "Docs": "", "Typewords": ["bool"] }, { "Name": "Draft", "Docs": "", "Typewords": ["bool"] }, { "Name": "Junk", "Docs": "", "Typewords": ["bool"] }, { "Name": "Sent", "Docs": "", "Typewords": ["bool"] }, { "Name": "Trash", "Docs": "", "Typewords": ["bool"] }, { "Name": "Keywords", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "HaveCounts", "Docs": "", "Typewords": ["bool"] }, { "Name": "Total", "Docs": "", "Typewords": ["int64"] }, { "Name": "Deleted", "Docs": "", "Typewords": ["int64"] }, { "Name": "Unread", "Docs": "", "Typewords": ["int64"] }, { "Name": "Unseen", "Docs": "", "Typewords": ["int64"] }, { "Name": "Size", "Docs": "", "Typewords": ["int64"] }] },
diff --git a/webmail/text.js b/webmail/text.js
index 1576476..7da4d37 100644
--- a/webmail/text.js
+++ b/webmail/text.js
@@ -306,7 +306,7 @@ var api;
 		"Domain": { "Name": "Domain", "Docs": "", "Fields": [{ "Name": "ASCII", "Docs": "", "Typewords": ["string"] }, { "Name": "Unicode", "Docs": "", "Typewords": ["string"] }] },
 		"FromAddressSettings": { "Name": "FromAddressSettings", "Docs": "", "Fields": [{ "Name": "FromAddress", "Docs": "", "Typewords": ["string"] }, { "Name": "ViewMode", "Docs": "", "Typewords": ["ViewMode"] }] },
 		"ComposeMessage": { "Name": "ComposeMessage", "Docs": "", "Fields": [{ "Name": "From", "Docs": "", "Typewords": ["string"] }, { "Name": "To", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "Cc", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "Bcc", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "ReplyTo", "Docs": "", "Typewords": ["string"] }, { "Name": "Subject", "Docs": "", "Typewords": ["string"] }, { "Name": "TextBody", "Docs": "", "Typewords": ["string"] }, { "Name": "ResponseMessageID", "Docs": "", "Typewords": ["int64"] }, { "Name": "DraftMessageID", "Docs": "", "Typewords": ["int64"] }] },
-		"SubmitMessage": { "Name": "SubmitMessage", "Docs": "", "Fields": [{ "Name": "From", "Docs": "", "Typewords": ["string"] }, { "Name": "To", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "Cc", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "Bcc", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "ReplyTo", "Docs": "", "Typewords": ["string"] }, { "Name": "Subject", "Docs": "", "Typewords": ["string"] }, { "Name": "TextBody", "Docs": "", "Typewords": ["string"] }, { "Name": "Attachments", "Docs": "", "Typewords": ["[]", "File"] }, { "Name": "ForwardAttachments", "Docs": "", "Typewords": ["ForwardAttachments"] }, { "Name": "IsForward", "Docs": "", "Typewords": ["bool"] }, { "Name": "ResponseMessageID", "Docs": "", "Typewords": ["int64"] }, { "Name": "UserAgent", "Docs": "", "Typewords": ["string"] }, { "Name": "RequireTLS", "Docs": "", "Typewords": ["nullable", "bool"] }, { "Name": "FutureRelease", "Docs": "", "Typewords": ["nullable", "timestamp"] }, { "Name": "ArchiveThread", "Docs": "", "Typewords": ["bool"] }, { "Name": "DraftMessageID", "Docs": "", "Typewords": ["int64"] }] },
+		"SubmitMessage": { "Name": "SubmitMessage", "Docs": "", "Fields": [{ "Name": "From", "Docs": "", "Typewords": ["string"] }, { "Name": "To", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "Cc", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "Bcc", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "ReplyTo", "Docs": "", "Typewords": ["string"] }, { "Name": "Subject", "Docs": "", "Typewords": ["string"] }, { "Name": "TextBody", "Docs": "", "Typewords": ["string"] }, { "Name": "Attachments", "Docs": "", "Typewords": ["[]", "File"] }, { "Name": "ForwardAttachments", "Docs": "", "Typewords": ["ForwardAttachments"] }, { "Name": "IsForward", "Docs": "", "Typewords": ["bool"] }, { "Name": "ResponseMessageID", "Docs": "", "Typewords": ["int64"] }, { "Name": "UserAgent", "Docs": "", "Typewords": ["string"] }, { "Name": "RequireTLS", "Docs": "", "Typewords": ["nullable", "bool"] }, { "Name": "FutureRelease", "Docs": "", "Typewords": ["nullable", "timestamp"] }, { "Name": "ArchiveThread", "Docs": "", "Typewords": ["bool"] }, { "Name": "ArchiveReferenceMailboxID", "Docs": "", "Typewords": ["int64"] }, { "Name": "DraftMessageID", "Docs": "", "Typewords": ["int64"] }] },
 		"File": { "Name": "File", "Docs": "", "Fields": [{ "Name": "Filename", "Docs": "", "Typewords": ["string"] }, { "Name": "DataURI", "Docs": "", "Typewords": ["string"] }] },
 		"ForwardAttachments": { "Name": "ForwardAttachments", "Docs": "", "Fields": [{ "Name": "MessageID", "Docs": "", "Typewords": ["int64"] }, { "Name": "Paths", "Docs": "", "Typewords": ["[]", "[]", "int32"] }] },
 		"Mailbox": { "Name": "Mailbox", "Docs": "", "Fields": [{ "Name": "ID", "Docs": "", "Typewords": ["int64"] }, { "Name": "Name", "Docs": "", "Typewords": ["string"] }, { "Name": "UIDValidity", "Docs": "", "Typewords": ["uint32"] }, { "Name": "UIDNext", "Docs": "", "Typewords": ["UID"] }, { "Name": "Archive", "Docs": "", "Typewords": ["bool"] }, { "Name": "Draft", "Docs": "", "Typewords": ["bool"] }, { "Name": "Junk", "Docs": "", "Typewords": ["bool"] }, { "Name": "Sent", "Docs": "", "Typewords": ["bool"] }, { "Name": "Trash", "Docs": "", "Typewords": ["bool"] }, { "Name": "Keywords", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "HaveCounts", "Docs": "", "Typewords": ["bool"] }, { "Name": "Total", "Docs": "", "Typewords": ["int64"] }, { "Name": "Deleted", "Docs": "", "Typewords": ["int64"] }, { "Name": "Unread", "Docs": "", "Typewords": ["int64"] }, { "Name": "Unseen", "Docs": "", "Typewords": ["int64"] }, { "Name": "Size", "Docs": "", "Typewords": ["int64"] }] },
diff --git a/webmail/webmail.js b/webmail/webmail.js
index cce8a83..c859276 100644
--- a/webmail/webmail.js
+++ b/webmail/webmail.js
@@ -306,7 +306,7 @@ var api;
 		"Domain": { "Name": "Domain", "Docs": "", "Fields": [{ "Name": "ASCII", "Docs": "", "Typewords": ["string"] }, { "Name": "Unicode", "Docs": "", "Typewords": ["string"] }] },
 		"FromAddressSettings": { "Name": "FromAddressSettings", "Docs": "", "Fields": [{ "Name": "FromAddress", "Docs": "", "Typewords": ["string"] }, { "Name": "ViewMode", "Docs": "", "Typewords": ["ViewMode"] }] },
 		"ComposeMessage": { "Name": "ComposeMessage", "Docs": "", "Fields": [{ "Name": "From", "Docs": "", "Typewords": ["string"] }, { "Name": "To", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "Cc", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "Bcc", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "ReplyTo", "Docs": "", "Typewords": ["string"] }, { "Name": "Subject", "Docs": "", "Typewords": ["string"] }, { "Name": "TextBody", "Docs": "", "Typewords": ["string"] }, { "Name": "ResponseMessageID", "Docs": "", "Typewords": ["int64"] }, { "Name": "DraftMessageID", "Docs": "", "Typewords": ["int64"] }] },
-		"SubmitMessage": { "Name": "SubmitMessage", "Docs": "", "Fields": [{ "Name": "From", "Docs": "", "Typewords": ["string"] }, { "Name": "To", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "Cc", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "Bcc", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "ReplyTo", "Docs": "", "Typewords": ["string"] }, { "Name": "Subject", "Docs": "", "Typewords": ["string"] }, { "Name": "TextBody", "Docs": "", "Typewords": ["string"] }, { "Name": "Attachments", "Docs": "", "Typewords": ["[]", "File"] }, { "Name": "ForwardAttachments", "Docs": "", "Typewords": ["ForwardAttachments"] }, { "Name": "IsForward", "Docs": "", "Typewords": ["bool"] }, { "Name": "ResponseMessageID", "Docs": "", "Typewords": ["int64"] }, { "Name": "UserAgent", "Docs": "", "Typewords": ["string"] }, { "Name": "RequireTLS", "Docs": "", "Typewords": ["nullable", "bool"] }, { "Name": "FutureRelease", "Docs": "", "Typewords": ["nullable", "timestamp"] }, { "Name": "ArchiveThread", "Docs": "", "Typewords": ["bool"] }, { "Name": "DraftMessageID", "Docs": "", "Typewords": ["int64"] }] },
+		"SubmitMessage": { "Name": "SubmitMessage", "Docs": "", "Fields": [{ "Name": "From", "Docs": "", "Typewords": ["string"] }, { "Name": "To", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "Cc", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "Bcc", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "ReplyTo", "Docs": "", "Typewords": ["string"] }, { "Name": "Subject", "Docs": "", "Typewords": ["string"] }, { "Name": "TextBody", "Docs": "", "Typewords": ["string"] }, { "Name": "Attachments", "Docs": "", "Typewords": ["[]", "File"] }, { "Name": "ForwardAttachments", "Docs": "", "Typewords": ["ForwardAttachments"] }, { "Name": "IsForward", "Docs": "", "Typewords": ["bool"] }, { "Name": "ResponseMessageID", "Docs": "", "Typewords": ["int64"] }, { "Name": "UserAgent", "Docs": "", "Typewords": ["string"] }, { "Name": "RequireTLS", "Docs": "", "Typewords": ["nullable", "bool"] }, { "Name": "FutureRelease", "Docs": "", "Typewords": ["nullable", "timestamp"] }, { "Name": "ArchiveThread", "Docs": "", "Typewords": ["bool"] }, { "Name": "ArchiveReferenceMailboxID", "Docs": "", "Typewords": ["int64"] }, { "Name": "DraftMessageID", "Docs": "", "Typewords": ["int64"] }] },
 		"File": { "Name": "File", "Docs": "", "Fields": [{ "Name": "Filename", "Docs": "", "Typewords": ["string"] }, { "Name": "DataURI", "Docs": "", "Typewords": ["string"] }] },
 		"ForwardAttachments": { "Name": "ForwardAttachments", "Docs": "", "Fields": [{ "Name": "MessageID", "Docs": "", "Typewords": ["int64"] }, { "Name": "Paths", "Docs": "", "Typewords": ["[]", "[]", "int32"] }] },
 		"Mailbox": { "Name": "Mailbox", "Docs": "", "Fields": [{ "Name": "ID", "Docs": "", "Typewords": ["int64"] }, { "Name": "Name", "Docs": "", "Typewords": ["string"] }, { "Name": "UIDValidity", "Docs": "", "Typewords": ["uint32"] }, { "Name": "UIDNext", "Docs": "", "Typewords": ["UID"] }, { "Name": "Archive", "Docs": "", "Typewords": ["bool"] }, { "Name": "Draft", "Docs": "", "Typewords": ["bool"] }, { "Name": "Junk", "Docs": "", "Typewords": ["bool"] }, { "Name": "Sent", "Docs": "", "Typewords": ["bool"] }, { "Name": "Trash", "Docs": "", "Typewords": ["bool"] }, { "Name": "Keywords", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "HaveCounts", "Docs": "", "Typewords": ["bool"] }, { "Name": "Total", "Docs": "", "Typewords": ["int64"] }, { "Name": "Deleted", "Docs": "", "Typewords": ["int64"] }, { "Name": "Unread", "Docs": "", "Typewords": ["int64"] }, { "Name": "Unseen", "Docs": "", "Typewords": ["int64"] }, { "Name": "Size", "Docs": "", "Typewords": ["int64"] }] },
@@ -2712,6 +2712,7 @@ const compose = (opts, listMailboxes) => {
 			RequireTLS: requiretls.value === '' ? null : requiretls.value === 'yes',
 			FutureRelease: scheduleTime.value ? new Date(scheduleTime.value) : null,
 			ArchiveThread: archive,
+			ArchiveReferenceMailboxID: opts.archiveReferenceMailboxID || 0,
 			DraftMessageID: draftMessageID,
 		};
 		await client.MessageSubmit(message);
@@ -3644,6 +3645,11 @@ const newMsgView = (miv, msglistView, listMailboxes, possibleLabels, messageLoad
 			responseMessageID: m.ID,
 			isList: m.IsMailingList,
 			editOffset: editOffset,
+			// For "send and archive", we only move messages from the current open mailbox
+			// (fallback to mailbox of response message for search results) to the archive
+			// mailbox. We don't want to move messages in other mailboxes, like Sent, Trash, or
+			// for cross-posted messages in other mailboxes.
+			archiveReferenceMailboxID: msglistView.activeMailbox()?.ID || m.MailboxID,
 		};
 		compose(opts, listMailboxes);
 	};
@@ -4090,7 +4096,7 @@ const newMsgView = (miv, msglistView, listMailboxes, possibleLabels, messageLoad
 	})();
 	return mv;
 };
-const newMsglistView = (msgElem, listMailboxes, setLocationHash, otherMailbox, possibleLabels, scrollElemHeight, refineKeyword, viewportEnsureMessages) => {
+const newMsglistView = (msgElem, activeMailbox, listMailboxes, setLocationHash, otherMailbox, possibleLabels, scrollElemHeight, refineKeyword, viewportEnsureMessages) => {
 	// msgitemViews holds all visible item views: All thread roots, and kids only if
 	// the thread is expanded, in order of descendants. All descendants of a collapsed
 	// root are in collapsedMsgitemViews, unsorted. Having msgitemViews as a list is
@@ -5359,6 +5365,7 @@ const newMsglistView = (msgElem, listMailboxes, setLocationHash, otherMailbox, p
 			}
 		},
 		mailboxes: () => listMailboxes(),
+		activeMailbox: () => activeMailbox(),
 		itemHeight: () => msgitemViews.length > 0 ? msgitemViews[0].root.getBoundingClientRect().height : 25,
 		threadExpand: (miv) => threadExpand(miv, true),
 		threadCollapse: (miv) => threadCollapse(miv, true),
@@ -6321,7 +6328,8 @@ const init = async () => {
 	};
 	const otherMailbox = (mailboxID) => requestFilter.MailboxID !== mailboxID ? (mailboxlistView.findMailboxByID(mailboxID) || null) : null;
 	const listMailboxes = () => mailboxlistView.mailboxes();
-	const msglistView = newMsglistView(msgElem, listMailboxes, setLocationHash, otherMailbox, possibleLabels, () => msglistscrollElem ? msglistscrollElem.getBoundingClientRect().height : 0, refineKeyword, viewportEnsureMessages);
+	const activeMailbox = () => mailboxlistView.activeMailbox();
+	const msglistView = newMsglistView(msgElem, activeMailbox, listMailboxes, setLocationHash, otherMailbox, possibleLabels, () => msglistscrollElem ? msglistscrollElem.getBoundingClientRect().height : 0, refineKeyword, viewportEnsureMessages);
 	const mailboxlistView = newMailboxlistView(msglistView, requestNewView, updatePageTitle, setLocationHash, unloadSearch, otherMailbox);
 	let refineUnreadBtn, refineReadBtn, refineAttachmentsBtn, refineLabelBtn;
 	const refineToggleActive = (btn) => {
diff --git a/webmail/webmail.ts b/webmail/webmail.ts
index 2e5755f..d90f1cc 100644
--- a/webmail/webmail.ts
+++ b/webmail/webmail.ts
@@ -1408,6 +1408,7 @@ type ComposeOptions = {
 	isList?: boolean
 	editOffset?: number // For cursor, default at start.
 	draftMessageID?: number // For composing for existing draft message, to be removed when message is sent.
+	archiveReferenceMailboxID?: number // For "send and archive", the mailbox from which to move messages to the archive mailbox.
 }
 
 interface ComposeView {
@@ -1613,6 +1614,7 @@ const compose = (opts: ComposeOptions, listMailboxes: listMailboxes) => {
 			RequireTLS: requiretls.value === '' ? null : requiretls.value === 'yes',
 			FutureRelease: scheduleTime.value ? new Date(scheduleTime.value) : null,
 			ArchiveThread: archive,
+			ArchiveReferenceMailboxID: opts.archiveReferenceMailboxID || 0,
 			DraftMessageID: draftMessageID,
 		}
 		await client.MessageSubmit(message)
@@ -2939,6 +2941,11 @@ const newMsgView = (miv: MsgitemView, msglistView: MsglistView, listMailboxes: l
 			responseMessageID: m.ID,
 			isList: m.IsMailingList,
 			editOffset: editOffset,
+			// For "send and archive", we only move messages from the current open mailbox
+			// (fallback to mailbox of response message for search results) to the archive
+			// mailbox. We don't want to move messages in other mailboxes, like Sent, Trash, or
+			// for cross-posted messages in other mailboxes.
+			archiveReferenceMailboxID: msglistView.activeMailbox()?.ID || m.MailboxID,
 		}
 		compose(opts, listMailboxes)
 	}
@@ -3625,6 +3632,7 @@ const newMsgView = (miv: MsgitemView, msglistView: MsglistView, listMailboxes: l
 // query is opened.
 interface MsglistView {
 	root: HTMLElement
+
 	updateFlags: (mailboxID: number, uid: number, modseq: number, mask: api.Flags, flags: api.Flags, keywords: string[]) => void
 	addMessageItems: (messageItems: (api.MessageItem[] | null)[], isChange: boolean, requestMsgID: number) => void
 	removeUIDs: (mailboxID: number, uids: number[]) => void
@@ -3639,6 +3647,7 @@ interface MsglistView {
 	click: (miv: MsgitemView, ctrl: boolean, shift: boolean) => void
 	key: (k: string, e: KeyboardEvent) => void
 	mailboxes: () => api.Mailbox[]
+	activeMailbox: () => api.Mailbox | null
 	itemHeight: () => number // For calculating how many messageitems to request to load next view.
 	threadExpand: (miv: MsgitemView) => void
 	threadCollapse: (miv: MsgitemView) => void
@@ -3657,7 +3666,7 @@ interface MsglistView {
 	cmdUnmute: () => Promise<void>
 }
 
-const newMsglistView = (msgElem: HTMLElement, listMailboxes: listMailboxes, setLocationHash: setLocationHash, otherMailbox: otherMailbox, possibleLabels: possibleLabels, scrollElemHeight: () => number, refineKeyword: (kw: string) => Promise<void>, viewportEnsureMessages: () => Promise<void>): MsglistView => {
+const newMsglistView = (msgElem: HTMLElement, activeMailbox: () => api.Mailbox | null, listMailboxes: listMailboxes, setLocationHash: setLocationHash, otherMailbox: otherMailbox, possibleLabels: possibleLabels, scrollElemHeight: () => number, refineKeyword: (kw: string) => Promise<void>, viewportEnsureMessages: () => Promise<void>): MsglistView => {
 	// msgitemViews holds all visible item views: All thread roots, and kids only if
 	// the thread is expanded, in order of descendants. All descendants of a collapsed
 	// root are in collapsedMsgitemViews, unsorted. Having msgitemViews as a list is
@@ -5000,6 +5009,7 @@ const newMsglistView = (msgElem: HTMLElement, listMailboxes: listMailboxes, setL
 			}
 		},
 		mailboxes: () => listMailboxes(),
+		activeMailbox: () => activeMailbox(),
 		itemHeight: () => msgitemViews.length > 0 ? msgitemViews[0].root.getBoundingClientRect().height : 25,
 		threadExpand: (miv: MsgitemView) => threadExpand(miv, true),
 		threadCollapse: (miv: MsgitemView) => threadCollapse(miv, true),
@@ -6361,7 +6371,8 @@ const init = async () => {
 
 	const otherMailbox = (mailboxID: number): api.Mailbox | null => requestFilter.MailboxID !== mailboxID ? (mailboxlistView.findMailboxByID(mailboxID) || null) : null
 	const listMailboxes = () => mailboxlistView.mailboxes()
-	const msglistView = newMsglistView(msgElem, listMailboxes, setLocationHash, otherMailbox, possibleLabels, () => msglistscrollElem ? msglistscrollElem.getBoundingClientRect().height : 0, refineKeyword, viewportEnsureMessages)
+	const activeMailbox = () => mailboxlistView.activeMailbox()
+	const msglistView = newMsglistView(msgElem, activeMailbox, listMailboxes, setLocationHash, otherMailbox, possibleLabels, () => msglistscrollElem ? msglistscrollElem.getBoundingClientRect().height : 0, refineKeyword, viewportEnsureMessages)
 	const mailboxlistView = newMailboxlistView(msglistView, requestNewView, updatePageTitle, setLocationHash, unloadSearch, otherMailbox)
 
 	let refineUnreadBtn: HTMLButtonElement, refineReadBtn: HTMLButtonElement, refineAttachmentsBtn: HTMLButtonElement, refineLabelBtn: HTMLButtonElement