diff --git a/apidiff/next.txt b/apidiff/next.txt
index e69de29..84f6fe9 100644
--- a/apidiff/next.txt
+++ b/apidiff/next.txt
@@ -0,0 +1,7 @@
+Below are the incompatible changes between v0.0.14 and next, per package.
+
+# message
+- Part.ContentDescription: changed from string to *string
+- Part.ContentID: changed from string to *string
+- Part.ContentTransferEncoding: changed from string to *string
+
diff --git a/dsn/dsn_test.go b/dsn/dsn_test.go
index 9fab9b8..ea6f3c2 100644
--- a/dsn/dsn_test.go
+++ b/dsn/dsn_test.go
@@ -50,8 +50,8 @@ func tcheckType(t *testing.T, p *message.Part, mt, mst, cte string) {
 	if !strings.EqualFold(p.MediaSubType, mst) {
 		t.Fatalf("got mediasubtype %q, expected %q", p.MediaSubType, mst)
 	}
-	if !strings.EqualFold(p.ContentTransferEncoding, cte) {
-		t.Fatalf("got content-transfer-encoding %q, expected %q", p.ContentTransferEncoding, cte)
+	if !(cte == "" && p.ContentTransferEncoding == nil || cte != "" && p.ContentTransferEncoding != nil && strings.EqualFold(cte, *p.ContentTransferEncoding)) {
+		t.Fatalf("got content-transfer-encoding %v, expected %v", p.ContentTransferEncoding, cte)
 	}
 }
 
diff --git a/imapserver/fetch.go b/imapserver/fetch.go
index feb1545..3042cf5 100644
--- a/imapserver/fetch.go
+++ b/imapserver/fetch.go
@@ -776,11 +776,15 @@ func (cmd *fetchCmd) xbinary(a fetchAtt) (string, token) {
 		cmd.xerrorf("binary only allowed on leaf parts, not multipart/* or message/rfc822 or message/global")
 	}
 
-	switch p.ContentTransferEncoding {
+	var cte string
+	if p.ContentTransferEncoding != nil {
+		cte = *p.ContentTransferEncoding
+	}
+	switch cte {
 	case "", "7BIT", "8BIT", "BINARY", "BASE64", "QUOTED-PRINTABLE":
 	default:
 		// ../rfc/9051:5913
-		xusercodeErrorf("UNKNOWN-CTE", "unknown Content-Transfer-Encoding %q", p.ContentTransferEncoding)
+		xusercodeErrorf("UNKNOWN-CTE", "unknown Content-Transfer-Encoding %q", cte)
 	}
 
 	r := p.Reader()
@@ -992,7 +996,11 @@ func bodyFldParams(p *message.Part) token {
 	return params
 }
 
-func bodyFldEnc(s string) token {
+func bodyFldEnc(cte *string) token {
+	var s string
+	if cte != nil {
+		s = *cte
+	}
 	up := strings.ToUpper(s)
 	switch up {
 	case "7BIT", "8BIT", "BINARY", "BASE64", "QUOTED-PRINTABLE":
@@ -1002,14 +1010,14 @@ func bodyFldEnc(s string) token {
 }
 
 func bodyFldMd5(p *message.Part) token {
-	if p.ContentMD5 == "" {
+	if p.ContentMD5 == nil {
 		return nilt
 	}
-	return string0(p.ContentMD5)
+	return string0(*p.ContentMD5)
 }
 
 func bodyFldDisp(log mlog.Log, p *message.Part) token {
-	if p.ContentDisposition == "" {
+	if p.ContentDisposition == nil {
 		return nilt
 	}
 
@@ -1019,12 +1027,12 @@ func bodyFldDisp(log mlog.Log, p *message.Part) token {
 	// And decodes character sets and removes language tags, like
 	// "title*0*=us-ascii'en'hello%20world. ../rfc/2231:210
 
-	disp, params, err := mime.ParseMediaType(p.ContentDisposition)
+	disp, params, err := mime.ParseMediaType(*p.ContentDisposition)
 	if err != nil {
-		log.Debugx("parsing content-disposition, ignoring", err, slog.String("header", p.ContentDisposition))
+		log.Debugx("parsing content-disposition, ignoring", err, slog.String("header", *p.ContentDisposition))
 		return nilt
 	} else if len(params) == 0 {
-		log.Debug("content-disposition has no parameters, ignoring", slog.String("header", p.ContentDisposition))
+		log.Debug("content-disposition has no parameters, ignoring", slog.String("header", *p.ContentDisposition))
 		return nilt
 	}
 	var fields listspace
@@ -1036,14 +1044,14 @@ func bodyFldDisp(log mlog.Log, p *message.Part) token {
 
 func bodyFldLang(p *message.Part) token {
 	// todo: ../rfc/3282:86 ../rfc/5646:218 we currently just split on comma and trim space, should properly parse header.
-	if p.ContentLanguage == "" {
+	if p.ContentLanguage == nil {
 		return nilt
 	}
 	var l listspace
-	for _, s := range strings.Split(p.ContentLanguage, ",") {
+	for _, s := range strings.Split(*p.ContentLanguage, ",") {
 		s = strings.TrimSpace(s)
 		if s == "" {
-			return string0(p.ContentLanguage)
+			return string0(*p.ContentLanguage)
 		}
 		l = append(l, string0(s))
 	}
@@ -1051,10 +1059,10 @@ func bodyFldLang(p *message.Part) token {
 }
 
 func bodyFldLoc(p *message.Part) token {
-	if p.ContentLocation == "" {
+	if p.ContentLocation == nil {
 		return nilt
 	}
-	return string0(p.ContentLocation)
+	return string0(*p.ContentLocation)
 }
 
 // xbodystructure returns a "body".
diff --git a/imapserver/pack.go b/imapserver/pack.go
index f6b934b..e68c415 100644
--- a/imapserver/pack.go
+++ b/imapserver/pack.go
@@ -34,11 +34,11 @@ func (t niltoken) xwriteTo(c *conn, xw io.Writer) {
 	xw.Write([]byte(t.pack(c)))
 }
 
-func nilOrString(s string) token {
-	if s == "" {
+func nilOrString(s *string) token {
+	if s == nil {
 		return nilt
 	}
-	return string0(s)
+	return string0(*s)
 }
 
 type string0 string
diff --git a/message/part.go b/message/part.go
index f05920b..3b586c1 100644
--- a/message/part.go
+++ b/message/part.go
@@ -65,14 +65,14 @@ type Part struct {
 	MediaType               string            // From Content-Type, upper case. E.g. "TEXT". Can be empty because content-type may be absent. In this case, the part may be treated as TEXT/PLAIN.
 	MediaSubType            string            // From Content-Type, upper case. E.g. "PLAIN".
 	ContentTypeParams       map[string]string // E.g. holds "boundary" for multipart messages. Has lower-case keys, and original case values.
-	ContentID               string
-	ContentDescription      string
-	ContentTransferEncoding string // In upper case.
-	ContentDisposition      string
-	ContentMD5              string
-	ContentLanguage         string
-	ContentLocation         string
-	Envelope                *Envelope // Email message headers. Not for non-message parts.
+	ContentID               *string           `json:",omitempty"`
+	ContentDescription      *string           `json:",omitempty"`
+	ContentTransferEncoding *string           `json:",omitempty"` // In upper case.
+	ContentDisposition      *string           `json:",omitempty"`
+	ContentMD5              *string           `json:",omitempty"`
+	ContentLanguage         *string           `json:",omitempty"`
+	ContentLocation         *string           `json:",omitempty"`
+	Envelope                *Envelope         `json:",omitempty"` // Email message headers. Not for non-message parts.
 
 	Parts []Part // Parts if this is a multipart.
 
@@ -362,13 +362,18 @@ func newPart(log mlog.Log, strict bool, r io.ReaderAt, offset int64, parent *Par
 		}
 	}
 
-	p.ContentID = p.header.Get("Content-Id")
-	p.ContentDescription = p.header.Get("Content-Description")
-	p.ContentTransferEncoding = strings.ToUpper(p.header.Get("Content-Transfer-Encoding"))
-	p.ContentDisposition = p.header.Get("Content-Disposition")
-	p.ContentMD5 = p.header.Get("Content-Md5")
-	p.ContentLanguage = p.header.Get("Content-Language")
-	p.ContentLocation = p.header.Get("Content-Location")
+	p.ContentID = p.headerGet("Content-Id")
+	p.ContentDescription = p.headerGet("Content-Description")
+	cte := p.headerGet("Content-Transfer-Encoding")
+	if cte != nil {
+		s := strings.ToUpper(*cte)
+		cte = &s
+	}
+	p.ContentTransferEncoding = cte
+	p.ContentDisposition = p.headerGet("Content-Disposition")
+	p.ContentMD5 = p.headerGet("Content-Md5")
+	p.ContentLanguage = p.headerGet("Content-Language")
+	p.ContentLocation = p.headerGet("Content-Location")
 
 	if parent == nil {
 		p.Envelope, err = parseEnvelope(log, mail.Header(p.header))
@@ -424,6 +429,15 @@ func (p *Part) Header() (textproto.MIMEHeader, error) {
 	return h, err
 }
 
+func (p *Part) headerGet(k string) *string {
+	l := p.header.Values(k)
+	if len(l) == 0 {
+		return nil
+	}
+	s := l[0]
+	return &s
+}
+
 // HeaderReader returns a reader for the header section of this part, including ending bare CRLF.
 func (p *Part) HeaderReader() io.Reader {
 	return io.NewSectionReader(p.r, p.HeaderOffset, p.BodyOffset-p.HeaderOffset)
@@ -657,17 +671,10 @@ var ErrParamEncoding = errors.New("bad header parameter encoding")
 // and a filename may still be returned.
 func (p *Part) DispositionFilename() (disposition string, filename string, err error) {
 	cd := p.ContentDisposition
-	if cd == "" {
-		h, err := p.Header()
-		if err != nil {
-			return "", "", fmt.Errorf("parsing header: %w", err)
-		}
-		cd = h.Get("Content-Disposition")
-	}
 	var disp string
 	var params map[string]string
-	if cd != "" {
-		disp, params, err = mime.ParseMediaType(cd)
+	if cd != nil && *cd != "" {
+		disp, params, err = mime.ParseMediaType(*cd)
 	}
 	if err != nil {
 		return "", "", fmt.Errorf("%w: parsing disposition header: %v", ErrParamEncoding, err)
@@ -786,9 +793,13 @@ func (tr *textReader) Read(buf []byte) (int, error) {
 	return o, nil
 }
 
-func newDecoder(cte string, r io.Reader) io.Reader {
+func newDecoder(cte *string, r io.Reader) io.Reader {
+	var s string
+	if cte != nil {
+		s = *cte
+	}
 	// ../rfc/2045:775
-	switch cte {
+	switch s {
 	case "BASE64":
 		return base64.NewDecoder(base64.StdEncoding, r)
 	case "QUOTED-PRINTABLE":
diff --git a/queue/hook.go b/queue/hook.go
index 1a9d526..43a5116 100644
--- a/queue/hook.go
+++ b/queue/hook.go
@@ -929,10 +929,14 @@ func PartStructure(log mlog.Log, p *message.Part) (webhook.Structure, error) {
 	} else if err != nil {
 		return webhook.Structure{}, err
 	}
+	var cid string
+	if p.ContentID != nil {
+		cid = *p.ContentID
+	}
 	s := webhook.Structure{
 		ContentType:        strings.ToLower(p.MediaType + "/" + p.MediaSubType),
 		ContentTypeParams:  p.ContentTypeParams,
-		ContentID:          p.ContentID,
+		ContentID:          cid,
 		ContentDisposition: strings.ToLower(disp),
 		Filename:           filename,
 		DecodedSize:        p.DecodedSize,
diff --git a/webmail/api.json b/webmail/api.json
index e20e724..b305f1c 100644
--- a/webmail/api.json
+++ b/webmail/api.json
@@ -1151,6 +1151,7 @@
 					"Name": "ContentID",
 					"Docs": "",
 					"Typewords": [
+						"nullable",
 						"string"
 					]
 				},
@@ -1158,6 +1159,7 @@
 					"Name": "ContentDescription",
 					"Docs": "",
 					"Typewords": [
+						"nullable",
 						"string"
 					]
 				},
@@ -1165,6 +1167,7 @@
 					"Name": "ContentTransferEncoding",
 					"Docs": "In upper case.",
 					"Typewords": [
+						"nullable",
 						"string"
 					]
 				},
@@ -1172,6 +1175,7 @@
 					"Name": "ContentDisposition",
 					"Docs": "",
 					"Typewords": [
+						"nullable",
 						"string"
 					]
 				},
@@ -1179,6 +1183,7 @@
 					"Name": "ContentMD5",
 					"Docs": "",
 					"Typewords": [
+						"nullable",
 						"string"
 					]
 				},
@@ -1186,6 +1191,7 @@
 					"Name": "ContentLanguage",
 					"Docs": "",
 					"Typewords": [
+						"nullable",
 						"string"
 					]
 				},
@@ -1193,6 +1199,7 @@
 					"Name": "ContentLocation",
 					"Docs": "",
 					"Typewords": [
+						"nullable",
 						"string"
 					]
 				},
diff --git a/webmail/api.ts b/webmail/api.ts
index 82f5958..201e18e 100644
--- a/webmail/api.ts
+++ b/webmail/api.ts
@@ -84,13 +84,13 @@ export interface Part {
 	MediaType: string  // From Content-Type, upper case. E.g. "TEXT". Can be empty because content-type may be absent. In this case, the part may be treated as TEXT/PLAIN.
 	MediaSubType: string  // From Content-Type, upper case. E.g. "PLAIN".
 	ContentTypeParams?: { [key: string]: string }  // E.g. holds "boundary" for multipart messages. Has lower-case keys, and original case values.
-	ContentID: string
-	ContentDescription: string
-	ContentTransferEncoding: string  // In upper case.
-	ContentDisposition: string
-	ContentMD5: string
-	ContentLanguage: string
-	ContentLocation: string
+	ContentID?: string | null
+	ContentDescription?: string | null
+	ContentTransferEncoding?: string | null  // In upper case.
+	ContentDisposition?: string | null
+	ContentMD5?: string | null
+	ContentLanguage?: string | null
+	ContentLocation?: string | null
 	Envelope?: Envelope | null  // Email message headers. Not for non-message parts.
 	Parts?: Part[] | null  // Parts if this is a multipart.
 	Message?: Part | null  // Only for message/rfc822 and message/global. This part may have a buffer as backing io.ReaderAt, because a message/global can have a non-identity content-transfer-encoding. This part has a nil parent.
@@ -617,7 +617,7 @@ export const types: TypenameMap = {
 	"NotFilter": {"Name":"NotFilter","Docs":"","Fields":[{"Name":"Words","Docs":"","Typewords":["[]","string"]},{"Name":"From","Docs":"","Typewords":["[]","string"]},{"Name":"To","Docs":"","Typewords":["[]","string"]},{"Name":"Subject","Docs":"","Typewords":["[]","string"]},{"Name":"Attachments","Docs":"","Typewords":["AttachmentType"]},{"Name":"Labels","Docs":"","Typewords":["[]","string"]}]},
 	"Page": {"Name":"Page","Docs":"","Fields":[{"Name":"AnchorMessageID","Docs":"","Typewords":["int64"]},{"Name":"Count","Docs":"","Typewords":["int32"]},{"Name":"DestMessageID","Docs":"","Typewords":["int64"]}]},
 	"ParsedMessage": {"Name":"ParsedMessage","Docs":"","Fields":[{"Name":"ID","Docs":"","Typewords":["int64"]},{"Name":"Part","Docs":"","Typewords":["Part"]},{"Name":"Headers","Docs":"","Typewords":["{}","[]","string"]},{"Name":"ViewMode","Docs":"","Typewords":["ViewMode"]},{"Name":"Texts","Docs":"","Typewords":["[]","string"]},{"Name":"HasHTML","Docs":"","Typewords":["bool"]},{"Name":"ListReplyAddress","Docs":"","Typewords":["nullable","MessageAddress"]},{"Name":"TextPaths","Docs":"","Typewords":["[]","[]","int32"]},{"Name":"HTMLPath","Docs":"","Typewords":["[]","int32"]}]},
-	"Part": {"Name":"Part","Docs":"","Fields":[{"Name":"BoundaryOffset","Docs":"","Typewords":["int64"]},{"Name":"HeaderOffset","Docs":"","Typewords":["int64"]},{"Name":"BodyOffset","Docs":"","Typewords":["int64"]},{"Name":"EndOffset","Docs":"","Typewords":["int64"]},{"Name":"RawLineCount","Docs":"","Typewords":["int64"]},{"Name":"DecodedSize","Docs":"","Typewords":["int64"]},{"Name":"MediaType","Docs":"","Typewords":["string"]},{"Name":"MediaSubType","Docs":"","Typewords":["string"]},{"Name":"ContentTypeParams","Docs":"","Typewords":["{}","string"]},{"Name":"ContentID","Docs":"","Typewords":["string"]},{"Name":"ContentDescription","Docs":"","Typewords":["string"]},{"Name":"ContentTransferEncoding","Docs":"","Typewords":["string"]},{"Name":"ContentDisposition","Docs":"","Typewords":["string"]},{"Name":"ContentMD5","Docs":"","Typewords":["string"]},{"Name":"ContentLanguage","Docs":"","Typewords":["string"]},{"Name":"ContentLocation","Docs":"","Typewords":["string"]},{"Name":"Envelope","Docs":"","Typewords":["nullable","Envelope"]},{"Name":"Parts","Docs":"","Typewords":["[]","Part"]},{"Name":"Message","Docs":"","Typewords":["nullable","Part"]}]},
+	"Part": {"Name":"Part","Docs":"","Fields":[{"Name":"BoundaryOffset","Docs":"","Typewords":["int64"]},{"Name":"HeaderOffset","Docs":"","Typewords":["int64"]},{"Name":"BodyOffset","Docs":"","Typewords":["int64"]},{"Name":"EndOffset","Docs":"","Typewords":["int64"]},{"Name":"RawLineCount","Docs":"","Typewords":["int64"]},{"Name":"DecodedSize","Docs":"","Typewords":["int64"]},{"Name":"MediaType","Docs":"","Typewords":["string"]},{"Name":"MediaSubType","Docs":"","Typewords":["string"]},{"Name":"ContentTypeParams","Docs":"","Typewords":["{}","string"]},{"Name":"ContentID","Docs":"","Typewords":["nullable","string"]},{"Name":"ContentDescription","Docs":"","Typewords":["nullable","string"]},{"Name":"ContentTransferEncoding","Docs":"","Typewords":["nullable","string"]},{"Name":"ContentDisposition","Docs":"","Typewords":["nullable","string"]},{"Name":"ContentMD5","Docs":"","Typewords":["nullable","string"]},{"Name":"ContentLanguage","Docs":"","Typewords":["nullable","string"]},{"Name":"ContentLocation","Docs":"","Typewords":["nullable","string"]},{"Name":"Envelope","Docs":"","Typewords":["nullable","Envelope"]},{"Name":"Parts","Docs":"","Typewords":["[]","Part"]},{"Name":"Message","Docs":"","Typewords":["nullable","Part"]}]},
 	"Envelope": {"Name":"Envelope","Docs":"","Fields":[{"Name":"Date","Docs":"","Typewords":["timestamp"]},{"Name":"Subject","Docs":"","Typewords":["string"]},{"Name":"From","Docs":"","Typewords":["[]","Address"]},{"Name":"Sender","Docs":"","Typewords":["[]","Address"]},{"Name":"ReplyTo","Docs":"","Typewords":["[]","Address"]},{"Name":"To","Docs":"","Typewords":["[]","Address"]},{"Name":"CC","Docs":"","Typewords":["[]","Address"]},{"Name":"BCC","Docs":"","Typewords":["[]","Address"]},{"Name":"InReplyTo","Docs":"","Typewords":["string"]},{"Name":"MessageID","Docs":"","Typewords":["string"]}]},
 	"Address": {"Name":"Address","Docs":"","Fields":[{"Name":"Name","Docs":"","Typewords":["string"]},{"Name":"User","Docs":"","Typewords":["string"]},{"Name":"Host","Docs":"","Typewords":["string"]}]},
 	"MessageAddress": {"Name":"MessageAddress","Docs":"","Fields":[{"Name":"Name","Docs":"","Typewords":["string"]},{"Name":"User","Docs":"","Typewords":["string"]},{"Name":"Domain","Docs":"","Typewords":["Domain"]}]},
diff --git a/webmail/msg.js b/webmail/msg.js
index 241b3b0..d28e6e2 100644
--- a/webmail/msg.js
+++ b/webmail/msg.js
@@ -299,7 +299,7 @@ var api;
 		"NotFilter": { "Name": "NotFilter", "Docs": "", "Fields": [{ "Name": "Words", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "From", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "To", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "Subject", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "Attachments", "Docs": "", "Typewords": ["AttachmentType"] }, { "Name": "Labels", "Docs": "", "Typewords": ["[]", "string"] }] },
 		"Page": { "Name": "Page", "Docs": "", "Fields": [{ "Name": "AnchorMessageID", "Docs": "", "Typewords": ["int64"] }, { "Name": "Count", "Docs": "", "Typewords": ["int32"] }, { "Name": "DestMessageID", "Docs": "", "Typewords": ["int64"] }] },
 		"ParsedMessage": { "Name": "ParsedMessage", "Docs": "", "Fields": [{ "Name": "ID", "Docs": "", "Typewords": ["int64"] }, { "Name": "Part", "Docs": "", "Typewords": ["Part"] }, { "Name": "Headers", "Docs": "", "Typewords": ["{}", "[]", "string"] }, { "Name": "ViewMode", "Docs": "", "Typewords": ["ViewMode"] }, { "Name": "Texts", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "HasHTML", "Docs": "", "Typewords": ["bool"] }, { "Name": "ListReplyAddress", "Docs": "", "Typewords": ["nullable", "MessageAddress"] }, { "Name": "TextPaths", "Docs": "", "Typewords": ["[]", "[]", "int32"] }, { "Name": "HTMLPath", "Docs": "", "Typewords": ["[]", "int32"] }] },
-		"Part": { "Name": "Part", "Docs": "", "Fields": [{ "Name": "BoundaryOffset", "Docs": "", "Typewords": ["int64"] }, { "Name": "HeaderOffset", "Docs": "", "Typewords": ["int64"] }, { "Name": "BodyOffset", "Docs": "", "Typewords": ["int64"] }, { "Name": "EndOffset", "Docs": "", "Typewords": ["int64"] }, { "Name": "RawLineCount", "Docs": "", "Typewords": ["int64"] }, { "Name": "DecodedSize", "Docs": "", "Typewords": ["int64"] }, { "Name": "MediaType", "Docs": "", "Typewords": ["string"] }, { "Name": "MediaSubType", "Docs": "", "Typewords": ["string"] }, { "Name": "ContentTypeParams", "Docs": "", "Typewords": ["{}", "string"] }, { "Name": "ContentID", "Docs": "", "Typewords": ["string"] }, { "Name": "ContentDescription", "Docs": "", "Typewords": ["string"] }, { "Name": "ContentTransferEncoding", "Docs": "", "Typewords": ["string"] }, { "Name": "ContentDisposition", "Docs": "", "Typewords": ["string"] }, { "Name": "ContentMD5", "Docs": "", "Typewords": ["string"] }, { "Name": "ContentLanguage", "Docs": "", "Typewords": ["string"] }, { "Name": "ContentLocation", "Docs": "", "Typewords": ["string"] }, { "Name": "Envelope", "Docs": "", "Typewords": ["nullable", "Envelope"] }, { "Name": "Parts", "Docs": "", "Typewords": ["[]", "Part"] }, { "Name": "Message", "Docs": "", "Typewords": ["nullable", "Part"] }] },
+		"Part": { "Name": "Part", "Docs": "", "Fields": [{ "Name": "BoundaryOffset", "Docs": "", "Typewords": ["int64"] }, { "Name": "HeaderOffset", "Docs": "", "Typewords": ["int64"] }, { "Name": "BodyOffset", "Docs": "", "Typewords": ["int64"] }, { "Name": "EndOffset", "Docs": "", "Typewords": ["int64"] }, { "Name": "RawLineCount", "Docs": "", "Typewords": ["int64"] }, { "Name": "DecodedSize", "Docs": "", "Typewords": ["int64"] }, { "Name": "MediaType", "Docs": "", "Typewords": ["string"] }, { "Name": "MediaSubType", "Docs": "", "Typewords": ["string"] }, { "Name": "ContentTypeParams", "Docs": "", "Typewords": ["{}", "string"] }, { "Name": "ContentID", "Docs": "", "Typewords": ["nullable", "string"] }, { "Name": "ContentDescription", "Docs": "", "Typewords": ["nullable", "string"] }, { "Name": "ContentTransferEncoding", "Docs": "", "Typewords": ["nullable", "string"] }, { "Name": "ContentDisposition", "Docs": "", "Typewords": ["nullable", "string"] }, { "Name": "ContentMD5", "Docs": "", "Typewords": ["nullable", "string"] }, { "Name": "ContentLanguage", "Docs": "", "Typewords": ["nullable", "string"] }, { "Name": "ContentLocation", "Docs": "", "Typewords": ["nullable", "string"] }, { "Name": "Envelope", "Docs": "", "Typewords": ["nullable", "Envelope"] }, { "Name": "Parts", "Docs": "", "Typewords": ["[]", "Part"] }, { "Name": "Message", "Docs": "", "Typewords": ["nullable", "Part"] }] },
 		"Envelope": { "Name": "Envelope", "Docs": "", "Fields": [{ "Name": "Date", "Docs": "", "Typewords": ["timestamp"] }, { "Name": "Subject", "Docs": "", "Typewords": ["string"] }, { "Name": "From", "Docs": "", "Typewords": ["[]", "Address"] }, { "Name": "Sender", "Docs": "", "Typewords": ["[]", "Address"] }, { "Name": "ReplyTo", "Docs": "", "Typewords": ["[]", "Address"] }, { "Name": "To", "Docs": "", "Typewords": ["[]", "Address"] }, { "Name": "CC", "Docs": "", "Typewords": ["[]", "Address"] }, { "Name": "BCC", "Docs": "", "Typewords": ["[]", "Address"] }, { "Name": "InReplyTo", "Docs": "", "Typewords": ["string"] }, { "Name": "MessageID", "Docs": "", "Typewords": ["string"] }] },
 		"Address": { "Name": "Address", "Docs": "", "Fields": [{ "Name": "Name", "Docs": "", "Typewords": ["string"] }, { "Name": "User", "Docs": "", "Typewords": ["string"] }, { "Name": "Host", "Docs": "", "Typewords": ["string"] }] },
 		"MessageAddress": { "Name": "MessageAddress", "Docs": "", "Fields": [{ "Name": "Name", "Docs": "", "Typewords": ["string"] }, { "Name": "User", "Docs": "", "Typewords": ["string"] }, { "Name": "Domain", "Docs": "", "Typewords": ["Domain"] }] },
diff --git a/webmail/text.js b/webmail/text.js
index 30f0056..8299644 100644
--- a/webmail/text.js
+++ b/webmail/text.js
@@ -299,7 +299,7 @@ var api;
 		"NotFilter": { "Name": "NotFilter", "Docs": "", "Fields": [{ "Name": "Words", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "From", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "To", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "Subject", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "Attachments", "Docs": "", "Typewords": ["AttachmentType"] }, { "Name": "Labels", "Docs": "", "Typewords": ["[]", "string"] }] },
 		"Page": { "Name": "Page", "Docs": "", "Fields": [{ "Name": "AnchorMessageID", "Docs": "", "Typewords": ["int64"] }, { "Name": "Count", "Docs": "", "Typewords": ["int32"] }, { "Name": "DestMessageID", "Docs": "", "Typewords": ["int64"] }] },
 		"ParsedMessage": { "Name": "ParsedMessage", "Docs": "", "Fields": [{ "Name": "ID", "Docs": "", "Typewords": ["int64"] }, { "Name": "Part", "Docs": "", "Typewords": ["Part"] }, { "Name": "Headers", "Docs": "", "Typewords": ["{}", "[]", "string"] }, { "Name": "ViewMode", "Docs": "", "Typewords": ["ViewMode"] }, { "Name": "Texts", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "HasHTML", "Docs": "", "Typewords": ["bool"] }, { "Name": "ListReplyAddress", "Docs": "", "Typewords": ["nullable", "MessageAddress"] }, { "Name": "TextPaths", "Docs": "", "Typewords": ["[]", "[]", "int32"] }, { "Name": "HTMLPath", "Docs": "", "Typewords": ["[]", "int32"] }] },
-		"Part": { "Name": "Part", "Docs": "", "Fields": [{ "Name": "BoundaryOffset", "Docs": "", "Typewords": ["int64"] }, { "Name": "HeaderOffset", "Docs": "", "Typewords": ["int64"] }, { "Name": "BodyOffset", "Docs": "", "Typewords": ["int64"] }, { "Name": "EndOffset", "Docs": "", "Typewords": ["int64"] }, { "Name": "RawLineCount", "Docs": "", "Typewords": ["int64"] }, { "Name": "DecodedSize", "Docs": "", "Typewords": ["int64"] }, { "Name": "MediaType", "Docs": "", "Typewords": ["string"] }, { "Name": "MediaSubType", "Docs": "", "Typewords": ["string"] }, { "Name": "ContentTypeParams", "Docs": "", "Typewords": ["{}", "string"] }, { "Name": "ContentID", "Docs": "", "Typewords": ["string"] }, { "Name": "ContentDescription", "Docs": "", "Typewords": ["string"] }, { "Name": "ContentTransferEncoding", "Docs": "", "Typewords": ["string"] }, { "Name": "ContentDisposition", "Docs": "", "Typewords": ["string"] }, { "Name": "ContentMD5", "Docs": "", "Typewords": ["string"] }, { "Name": "ContentLanguage", "Docs": "", "Typewords": ["string"] }, { "Name": "ContentLocation", "Docs": "", "Typewords": ["string"] }, { "Name": "Envelope", "Docs": "", "Typewords": ["nullable", "Envelope"] }, { "Name": "Parts", "Docs": "", "Typewords": ["[]", "Part"] }, { "Name": "Message", "Docs": "", "Typewords": ["nullable", "Part"] }] },
+		"Part": { "Name": "Part", "Docs": "", "Fields": [{ "Name": "BoundaryOffset", "Docs": "", "Typewords": ["int64"] }, { "Name": "HeaderOffset", "Docs": "", "Typewords": ["int64"] }, { "Name": "BodyOffset", "Docs": "", "Typewords": ["int64"] }, { "Name": "EndOffset", "Docs": "", "Typewords": ["int64"] }, { "Name": "RawLineCount", "Docs": "", "Typewords": ["int64"] }, { "Name": "DecodedSize", "Docs": "", "Typewords": ["int64"] }, { "Name": "MediaType", "Docs": "", "Typewords": ["string"] }, { "Name": "MediaSubType", "Docs": "", "Typewords": ["string"] }, { "Name": "ContentTypeParams", "Docs": "", "Typewords": ["{}", "string"] }, { "Name": "ContentID", "Docs": "", "Typewords": ["nullable", "string"] }, { "Name": "ContentDescription", "Docs": "", "Typewords": ["nullable", "string"] }, { "Name": "ContentTransferEncoding", "Docs": "", "Typewords": ["nullable", "string"] }, { "Name": "ContentDisposition", "Docs": "", "Typewords": ["nullable", "string"] }, { "Name": "ContentMD5", "Docs": "", "Typewords": ["nullable", "string"] }, { "Name": "ContentLanguage", "Docs": "", "Typewords": ["nullable", "string"] }, { "Name": "ContentLocation", "Docs": "", "Typewords": ["nullable", "string"] }, { "Name": "Envelope", "Docs": "", "Typewords": ["nullable", "Envelope"] }, { "Name": "Parts", "Docs": "", "Typewords": ["[]", "Part"] }, { "Name": "Message", "Docs": "", "Typewords": ["nullable", "Part"] }] },
 		"Envelope": { "Name": "Envelope", "Docs": "", "Fields": [{ "Name": "Date", "Docs": "", "Typewords": ["timestamp"] }, { "Name": "Subject", "Docs": "", "Typewords": ["string"] }, { "Name": "From", "Docs": "", "Typewords": ["[]", "Address"] }, { "Name": "Sender", "Docs": "", "Typewords": ["[]", "Address"] }, { "Name": "ReplyTo", "Docs": "", "Typewords": ["[]", "Address"] }, { "Name": "To", "Docs": "", "Typewords": ["[]", "Address"] }, { "Name": "CC", "Docs": "", "Typewords": ["[]", "Address"] }, { "Name": "BCC", "Docs": "", "Typewords": ["[]", "Address"] }, { "Name": "InReplyTo", "Docs": "", "Typewords": ["string"] }, { "Name": "MessageID", "Docs": "", "Typewords": ["string"] }] },
 		"Address": { "Name": "Address", "Docs": "", "Fields": [{ "Name": "Name", "Docs": "", "Typewords": ["string"] }, { "Name": "User", "Docs": "", "Typewords": ["string"] }, { "Name": "Host", "Docs": "", "Typewords": ["string"] }] },
 		"MessageAddress": { "Name": "MessageAddress", "Docs": "", "Fields": [{ "Name": "Name", "Docs": "", "Typewords": ["string"] }, { "Name": "User", "Docs": "", "Typewords": ["string"] }, { "Name": "Domain", "Docs": "", "Typewords": ["Domain"] }] },
diff --git a/webmail/webmail.go b/webmail/webmail.go
index 7948056..0693e8c 100644
--- a/webmail/webmail.go
+++ b/webmail/webmail.go
@@ -898,7 +898,7 @@ func inlineSanitizeHTML(log mlog.Log, setHeaders func(), w io.Writer, p *message
 func findCID(p *message.Part, parents []*message.Part, cid string) *message.Part {
 	for i := len(parents) - 1; i >= 0; i-- {
 		for j, pp := range parents[i].Parts {
-			if strings.EqualFold(pp.ContentID, cid) {
+			if pp.ContentID != nil && strings.EqualFold(*pp.ContentID, cid) {
 				return &parents[i].Parts[j]
 			}
 		}
@@ -911,7 +911,7 @@ func findCID(p *message.Part, parents []*message.Part, cid string) *message.Part
 }
 
 func findCIDAll(p *message.Part, cid string) *message.Part {
-	if strings.EqualFold(p.ContentID, cid) {
+	if p.ContentID != nil && strings.EqualFold(*p.ContentID, cid) {
 		return p
 	}
 	for i := range p.Parts {
diff --git a/webmail/webmail.js b/webmail/webmail.js
index 4bf9b40..cf41deb 100644
--- a/webmail/webmail.js
+++ b/webmail/webmail.js
@@ -299,7 +299,7 @@ var api;
 		"NotFilter": { "Name": "NotFilter", "Docs": "", "Fields": [{ "Name": "Words", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "From", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "To", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "Subject", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "Attachments", "Docs": "", "Typewords": ["AttachmentType"] }, { "Name": "Labels", "Docs": "", "Typewords": ["[]", "string"] }] },
 		"Page": { "Name": "Page", "Docs": "", "Fields": [{ "Name": "AnchorMessageID", "Docs": "", "Typewords": ["int64"] }, { "Name": "Count", "Docs": "", "Typewords": ["int32"] }, { "Name": "DestMessageID", "Docs": "", "Typewords": ["int64"] }] },
 		"ParsedMessage": { "Name": "ParsedMessage", "Docs": "", "Fields": [{ "Name": "ID", "Docs": "", "Typewords": ["int64"] }, { "Name": "Part", "Docs": "", "Typewords": ["Part"] }, { "Name": "Headers", "Docs": "", "Typewords": ["{}", "[]", "string"] }, { "Name": "ViewMode", "Docs": "", "Typewords": ["ViewMode"] }, { "Name": "Texts", "Docs": "", "Typewords": ["[]", "string"] }, { "Name": "HasHTML", "Docs": "", "Typewords": ["bool"] }, { "Name": "ListReplyAddress", "Docs": "", "Typewords": ["nullable", "MessageAddress"] }, { "Name": "TextPaths", "Docs": "", "Typewords": ["[]", "[]", "int32"] }, { "Name": "HTMLPath", "Docs": "", "Typewords": ["[]", "int32"] }] },
-		"Part": { "Name": "Part", "Docs": "", "Fields": [{ "Name": "BoundaryOffset", "Docs": "", "Typewords": ["int64"] }, { "Name": "HeaderOffset", "Docs": "", "Typewords": ["int64"] }, { "Name": "BodyOffset", "Docs": "", "Typewords": ["int64"] }, { "Name": "EndOffset", "Docs": "", "Typewords": ["int64"] }, { "Name": "RawLineCount", "Docs": "", "Typewords": ["int64"] }, { "Name": "DecodedSize", "Docs": "", "Typewords": ["int64"] }, { "Name": "MediaType", "Docs": "", "Typewords": ["string"] }, { "Name": "MediaSubType", "Docs": "", "Typewords": ["string"] }, { "Name": "ContentTypeParams", "Docs": "", "Typewords": ["{}", "string"] }, { "Name": "ContentID", "Docs": "", "Typewords": ["string"] }, { "Name": "ContentDescription", "Docs": "", "Typewords": ["string"] }, { "Name": "ContentTransferEncoding", "Docs": "", "Typewords": ["string"] }, { "Name": "ContentDisposition", "Docs": "", "Typewords": ["string"] }, { "Name": "ContentMD5", "Docs": "", "Typewords": ["string"] }, { "Name": "ContentLanguage", "Docs": "", "Typewords": ["string"] }, { "Name": "ContentLocation", "Docs": "", "Typewords": ["string"] }, { "Name": "Envelope", "Docs": "", "Typewords": ["nullable", "Envelope"] }, { "Name": "Parts", "Docs": "", "Typewords": ["[]", "Part"] }, { "Name": "Message", "Docs": "", "Typewords": ["nullable", "Part"] }] },
+		"Part": { "Name": "Part", "Docs": "", "Fields": [{ "Name": "BoundaryOffset", "Docs": "", "Typewords": ["int64"] }, { "Name": "HeaderOffset", "Docs": "", "Typewords": ["int64"] }, { "Name": "BodyOffset", "Docs": "", "Typewords": ["int64"] }, { "Name": "EndOffset", "Docs": "", "Typewords": ["int64"] }, { "Name": "RawLineCount", "Docs": "", "Typewords": ["int64"] }, { "Name": "DecodedSize", "Docs": "", "Typewords": ["int64"] }, { "Name": "MediaType", "Docs": "", "Typewords": ["string"] }, { "Name": "MediaSubType", "Docs": "", "Typewords": ["string"] }, { "Name": "ContentTypeParams", "Docs": "", "Typewords": ["{}", "string"] }, { "Name": "ContentID", "Docs": "", "Typewords": ["nullable", "string"] }, { "Name": "ContentDescription", "Docs": "", "Typewords": ["nullable", "string"] }, { "Name": "ContentTransferEncoding", "Docs": "", "Typewords": ["nullable", "string"] }, { "Name": "ContentDisposition", "Docs": "", "Typewords": ["nullable", "string"] }, { "Name": "ContentMD5", "Docs": "", "Typewords": ["nullable", "string"] }, { "Name": "ContentLanguage", "Docs": "", "Typewords": ["nullable", "string"] }, { "Name": "ContentLocation", "Docs": "", "Typewords": ["nullable", "string"] }, { "Name": "Envelope", "Docs": "", "Typewords": ["nullable", "Envelope"] }, { "Name": "Parts", "Docs": "", "Typewords": ["[]", "Part"] }, { "Name": "Message", "Docs": "", "Typewords": ["nullable", "Part"] }] },
 		"Envelope": { "Name": "Envelope", "Docs": "", "Fields": [{ "Name": "Date", "Docs": "", "Typewords": ["timestamp"] }, { "Name": "Subject", "Docs": "", "Typewords": ["string"] }, { "Name": "From", "Docs": "", "Typewords": ["[]", "Address"] }, { "Name": "Sender", "Docs": "", "Typewords": ["[]", "Address"] }, { "Name": "ReplyTo", "Docs": "", "Typewords": ["[]", "Address"] }, { "Name": "To", "Docs": "", "Typewords": ["[]", "Address"] }, { "Name": "CC", "Docs": "", "Typewords": ["[]", "Address"] }, { "Name": "BCC", "Docs": "", "Typewords": ["[]", "Address"] }, { "Name": "InReplyTo", "Docs": "", "Typewords": ["string"] }, { "Name": "MessageID", "Docs": "", "Typewords": ["string"] }] },
 		"Address": { "Name": "Address", "Docs": "", "Fields": [{ "Name": "Name", "Docs": "", "Typewords": ["string"] }, { "Name": "User", "Docs": "", "Typewords": ["string"] }, { "Name": "Host", "Docs": "", "Typewords": ["string"] }] },
 		"MessageAddress": { "Name": "MessageAddress", "Docs": "", "Fields": [{ "Name": "Name", "Docs": "", "Typewords": ["string"] }, { "Name": "User", "Docs": "", "Typewords": ["string"] }, { "Name": "Domain", "Docs": "", "Typewords": ["Domain"] }] },