fix: preserve signature styling and reactivity in above-quote mode #272

app/[locale]/page.tsx

@@ -1659,7 +1659,9 @@ export default function Home() {
 
     // Append signature from the sending identity (fall back to primary
     // when the reply-from lives on the same identity but a different alias).
-    const finalBody = appendPlainTextSignature(body, sendingIdentity);
+    const finalBody = appendPlainTextSignature(body, sendingIdentity, {
+      separator: useSettingsStore.getState().signatureSeparatorEnabled,
+    });
 
     const originalEmailId = selectedEmail.id;
 

components/email/email-composer.tsx

@@ -35,6 +35,7 @@ import { appendPlainTextSignature, getPlainTextSignature } from "@/lib/signature
 import { resolveReplyFrom } from "@/lib/reply-identity";
 import { computeReplyThreadingHeaders } from "@/lib/email-threading";
 import { RichTextEditor } from "@/components/email/rich-text-editor";
+import type { Editor } from "@tiptap/react";
 
 /** Strip HTML tags and decode entities to get a plain-text version */
 function htmlToPlainText(html: string): string {
@@ -116,6 +117,39 @@ type ComposerAttachment = {
   abortController?: AbortController;
 };
 
+type SignatureIdentityLike = {
+  htmlSignature?: string;
+  textSignature?: string;
+} | null | undefined;
+
+// Render the embedded signature for "above quote" mode. Bracketed with
+// `data-signature-block` marker paragraphs so we can swap the inner content
+// when the user switches identity without losing the surrounding draft or
+// quoted message. The markers are preserved through TipTap by the
+// StyledParagraph extension.
+function buildEmbeddedSignatureHtml(
+  identity: SignatureIdentityLike,
+  options: { embed: boolean; separator: boolean }
+): string {
+  if (!options.embed) return '';
+  const startMarker = options.separator
+    ? `<p data-signature-block="separator">-- </p>`
+    : `<p data-signature-block="start"></p>`;
+  const endMarker = `<p data-signature-block="end"></p>`;
+  if (identity?.htmlSignature) {
+    return `${startMarker}${sanitizeEmailHtml(identity.htmlSignature)}${endMarker}`;
+  }
+  if (identity?.textSignature) {
+    const escaped = identity.textSignature
+      .replace(/&/g, '&amp;')
+      .replace(/</g, '&lt;')
+      .replace(/>/g, '&gt;')
+      .replace(/\n/g, '<br>');
+    return `${startMarker}<p>${escaped}</p>${endMarker}`;
+  }
+  return '';
+}
+
 export function EmailComposer({
   onSend,
   onClose,
@@ -136,6 +170,7 @@ export function EmailComposer({
   const attachmentReminderEnabled = useSettingsStore((state) => state.attachmentReminderEnabled);
   const attachmentReminderKeywords = useSettingsStore((state) => state.attachmentReminderKeywords);
   const signaturePosition = useSettingsStore((state) => state.signaturePosition);
+  const signatureSeparatorEnabled = useSettingsStore((state) => state.signatureSeparatorEnabled);
   const identities = useIdentityStore((s) => s.identities);
   const primaryIdentity = identities[0] ?? null;
 
@@ -206,8 +241,9 @@ export function EmailComposer({
       // drafting area and the quoted content so it reads naturally as a
       // closing for the reply body. Send-time append is skipped — see
       // shouldEmbedSignatureAboveQuote.
+      const plainSep = signatureSeparatorEnabled ? '\n\n-- \n' : '\n\n';
       const signatureBlock = shouldEmbedSignatureAboveQuote
-        ? `\n\n-- \n${getPlainTextSignature(initialSignatureIdentity)}`
+        ? `${plainSep}${getPlainTextSignature(initialSignatureIdentity)}`
         : '';
 
       if (mode === 'forward') {
@@ -225,21 +261,10 @@ export function EmailComposer({
     const from = replyTo.from?.[0];
     const fromStr = from ? `${from.name || from.email}` : tCommon('unknown');
 
-    // When "above quote" is configured, splice signature between the user's
-    // drafting area and the quoted content so it reads naturally as a closing
-    // for the reply body. Send-time append is skipped — see
-    // shouldEmbedSignatureAboveQuote.
-    const buildEmbeddedSignatureHtml = (): string => {
-      if (!shouldEmbedSignatureAboveQuote) return '';
-      if (initialSignatureIdentity?.htmlSignature) {
-        return `<br><br>-- <br>${sanitizeEmailHtml(initialSignatureIdentity.htmlSignature)}`;
-      }
-      if (initialSignatureIdentity?.textSignature) {
-        return `<br><br>-- <br>${initialSignatureIdentity.textSignature.replace(/&/g, '&amp;').replace(/</g, '&lt;').replace(/>/g, '&gt;').replace(/\n/g, '<br>')}`;
-      }
-      return '';
-    };
-    const signatureBlock = buildEmbeddedSignatureHtml();
+    const signatureBlock = buildEmbeddedSignatureHtml(initialSignatureIdentity, {
+      embed: shouldEmbedSignatureAboveQuote,
+      separator: signatureSeparatorEnabled,
+    });
 
     // Build quoted content as HTML
     if (replyTo.htmlBody && (mode === 'reply' || mode === 'replyAll' || mode === 'forward')) {
@@ -335,6 +360,69 @@ export function EmailComposer({
   const signatureIdentity = (currentIdentity?.htmlSignature || currentIdentity?.textSignature)
     ? currentIdentity
     : primaryIdentity;
+
+  // Hold the TipTap editor instance so we can swap the embedded signature
+  // when the user switches identity in "above quote" mode without rebuilding
+  // the whole body (which would lose user edits to the surrounding draft).
+  const editorRef = useRef<Editor | null>(null);
+  const prevSignatureIdentityIdRef = useRef<string | null | undefined>(signatureIdentity?.id);
+  const prevSignatureSeparatorRef = useRef<boolean>(signatureSeparatorEnabled);
+
+  useEffect(() => {
+    const editor = editorRef.current;
+    const identityChanged = prevSignatureIdentityIdRef.current !== signatureIdentity?.id;
+    const separatorChanged = prevSignatureSeparatorRef.current !== signatureSeparatorEnabled;
+    prevSignatureIdentityIdRef.current = signatureIdentity?.id;
+    prevSignatureSeparatorRef.current = signatureSeparatorEnabled;
+    if (!editor) return;
+    if (!identityChanged && !separatorChanged) return;
+    if (plainTextMode) return;
+    if (mode !== 'reply' && mode !== 'replyAll' && mode !== 'forward') return;
+    if (signaturePosition !== 'above_quote') return;
+
+    const currentHtml = editor.getHTML();
+    const doc = new DOMParser().parseFromString(currentHtml, 'text/html');
+    const startEl = doc.querySelector('[data-signature-block="separator"], [data-signature-block="start"]');
+    if (!startEl) return;
+    const endEl = doc.querySelector('[data-signature-block="end"]');
+
+    const newSignature = buildEmbeddedSignatureHtml(signatureIdentity, {
+      embed: true,
+      separator: signatureSeparatorEnabled,
+    });
+    if (!newSignature) return;
+
+    // Build a temporary container holding the replacement nodes so we can
+    // splice them in without re-serializing/parsing twice.
+    const replacementHost = doc.createElement('div');
+    replacementHost.innerHTML = newSignature;
+    const replacementNodes = Array.from(replacementHost.childNodes);
+
+    const parent = startEl.parentNode;
+    if (!parent) return;
+
+    // Remove the existing signature range [startEl … endEl] inclusive, or
+    // from startEl to the next blockquote if no end marker is present.
+    const removeUntil = endEl && endEl.parentNode === parent ? endEl : null;
+    let cursor: ChildNode | null = startEl;
+    const toRemove: ChildNode[] = [];
+    while (cursor) {
+      toRemove.push(cursor);
+      if (cursor === removeUntil) break;
+      const next: ChildNode | null = cursor.nextSibling;
+      if (!removeUntil && next && (next as Element).tagName === 'BLOCKQUOTE') break;
+      cursor = next;
+    }
+    const insertBefore = toRemove[toRemove.length - 1]?.nextSibling ?? null;
+    toRemove.forEach((node) => parent.removeChild(node));
+    replacementNodes.forEach((node) => parent.insertBefore(node, insertBefore));
+
+    const nextHtml = doc.body.innerHTML;
+    if (nextHtml !== currentHtml) {
+      editor.commands.setContent(nextHtml, { emitUpdate: true });
+    }
+  }, [signatureIdentity?.id, signatureIdentity?.htmlSignature, signatureIdentity?.textSignature, signatureSeparatorEnabled, signaturePosition, mode, plainTextMode]);
+
   useEffect(() => {
     if (!autoSelectReplyIdentity) return;
     if (selectedIdentityId || initialData?.selectedIdentityId) return;
@@ -1038,11 +1126,12 @@ export function EmailComposer({
     // Build HTML signature block (used only in rich text mode)
     const buildSignatureHtml = (): string => {
       if (signatureAlreadyInBody) return '';
+      const sep = signatureSeparatorEnabled ? `<br><br>-- <br>` : `<br><br>`;
       if (signatureIdentity?.htmlSignature) {
-        return `<br><br>-- <br>${sanitizeEmailHtml(signatureIdentity.htmlSignature)}`;
+        return `${sep}${sanitizeEmailHtml(signatureIdentity.htmlSignature)}`;
       }
       if (signatureIdentity?.textSignature) {
-        return `<br><br>-- <br>${signatureIdentity.textSignature.replace(/&/g, '&amp;').replace(/</g, '&lt;').replace(/>/g, '&gt;').replace(/\n/g, '<br>')}`;
+        return `${sep}${signatureIdentity.textSignature.replace(/&/g, '&amp;').replace(/</g, '&lt;').replace(/>/g, '&gt;').replace(/\n/g, '<br>')}`;
       }
       return '';
     };
@@ -1053,9 +1142,10 @@ export function EmailComposer({
       : null;
 
     // In plain text mode, send text/plain only (no HTML body)
+    const signatureOpts = { separator: signatureSeparatorEnabled };
     const finalBody = plainTextMode
-      ? (signatureAlreadyInBody ? body : appendPlainTextSignature(body, signatureIdentity))
-      : (signatureAlreadyInBody ? htmlToPlainText(body) : appendPlainTextSignature(htmlToPlainText(body), signatureIdentity));
+      ? (signatureAlreadyInBody ? body : appendPlainTextSignature(body, signatureIdentity, signatureOpts))
+      : (signatureAlreadyInBody ? htmlToPlainText(body) : appendPlainTextSignature(htmlToPlainText(body), signatureIdentity, signatureOpts));
 
     const rewritten = plainTextMode ? null : rewriteInlineImages(body);
     const finalHtmlBody = plainTextMode
@@ -1628,6 +1718,7 @@ export function EmailComposer({
               onImageUpload={handleImageUpload}
               placeholder={t('body_placeholder')}
               hasError={validationErrors.body}
+              onEditorReady={(ed) => { editorRef.current = ed; }}
             />
           </div>
         )}
@@ -1638,13 +1729,13 @@ export function EmailComposer({
           : plainTextMode ? (
           getPlainTextSignature(signatureIdentity) ? (
             <div className="px-4 pb-3 text-sm leading-6 text-muted-foreground break-words whitespace-pre-wrap font-mono">
-              {'-- \n'}{getPlainTextSignature(signatureIdentity)}
+              {signatureSeparatorEnabled ? '-- \n' : ''}{getPlainTextSignature(signatureIdentity)}
             </div>
           ) : null
         ) : composerSignatureHtml ? (
           <div
             className="px-4 pb-3 text-sm leading-6 text-foreground break-words [&_a]:text-primary [&_a]:underline-offset-2 [&_a:hover]:underline"
-            dangerouslySetInnerHTML={{ __html: `<div>-- </div>${composerSignatureHtml}` }}
+            dangerouslySetInnerHTML={{ __html: `${signatureSeparatorEnabled ? '<div>-- </div>' : ''}${composerSignatureHtml}` }}
           />
         ) : null}
       </div>

components/email/rich-text-editor.tsx

@@ -1,8 +1,10 @@
 "use client";
 
 import React, { useEffect, useCallback, useState, useRef } from "react";
-import { useEditor, EditorContent } from "@tiptap/react";
+import { useEditor, EditorContent, type Editor } from "@tiptap/react";
 import StarterKit from "@tiptap/starter-kit";
+import Paragraph from "@tiptap/extension-paragraph";
+import Heading from "@tiptap/extension-heading";
 import Underline from "@tiptap/extension-underline";
 import Link from "@tiptap/extension-link";
 import TextAlign from "@tiptap/extension-text-align";
@@ -44,6 +46,51 @@ export interface InlineImageUpload {
   cid?: string;
 }
 
+// Pasted email content (signatures, replies, quoted text) commonly carries
+// inline styles on block elements. StarterKit's default Paragraph/Heading
+// drop unknown attributes; extend them to round-trip `style` and `class` so
+// signature formatting survives the editor.
+const styledBlockAttributes = {
+  style: {
+    default: null as string | null,
+    parseHTML: (el: HTMLElement) => el.getAttribute("style"),
+    renderHTML: (attrs: Record<string, string | null>) =>
+      attrs.style ? { style: attrs.style } : {},
+  },
+  class: {
+    default: null as string | null,
+    parseHTML: (el: HTMLElement) => el.getAttribute("class"),
+    renderHTML: (attrs: Record<string, string | null>) =>
+      attrs.class ? { class: attrs.class } : {},
+  },
+  "data-signature-block": {
+    default: null as string | null,
+    parseHTML: (el: HTMLElement) => el.getAttribute("data-signature-block"),
+    renderHTML: (attrs: Record<string, string | null>) =>
+      attrs["data-signature-block"]
+        ? { "data-signature-block": attrs["data-signature-block"] }
+        : {},
+  },
+};
+
+const StyledParagraph = Paragraph.extend({
+  addAttributes() {
+    return {
+      ...this.parent?.(),
+      ...styledBlockAttributes,
+    };
+  },
+});
+
+const StyledHeading = Heading.extend({
+  addAttributes() {
+    return {
+      ...this.parent?.(),
+      ...styledBlockAttributes,
+    };
+  },
+});
+
 interface RichTextEditorProps {
   content: string;
   onChange: (html: string) => void;
@@ -51,6 +98,7 @@ interface RichTextEditorProps {
   placeholder?: string;
   className?: string;
   hasError?: boolean;
+  onEditorReady?: (editor: Editor) => void;
 }
 
 function ToolbarButton({
@@ -131,17 +179,23 @@ export function RichTextEditor({
   placeholder,
   className,
   hasError,
+  onEditorReady,
 }: RichTextEditorProps) {
   const onImageUploadRef = React.useRef(onImageUpload);
   onImageUploadRef.current = onImageUpload;
+  const onEditorReadyRef = React.useRef(onEditorReady);
+  onEditorReadyRef.current = onEditorReady;
 
   const editor = useEditor({
     extensions: [
       StarterKit.configure({
-        heading: { levels: [1, 2] },
+        heading: false,
+        paragraph: false,
         link: false,
         underline: false,
       }),
+      StyledParagraph,
+      StyledHeading.configure({ levels: [1, 2] }),
       Underline,
       Link.configure({
         openOnClick: false,
@@ -239,6 +293,12 @@ export function RichTextEditor({
     }
   }, [content, editor]);
 
+  // Expose the editor instance once it's ready so parents can target
+  // specific nodes (e.g. swap the embedded signature on identity change).
+  useEffect(() => {
+    if (editor) onEditorReadyRef.current?.(editor);
+  }, [editor]);
+
   const addLink = useCallback(() => {
     if (!editor) return;
     const previousUrl = editor.getAttributes("link").href;

components/settings/composing-settings.tsx

@@ -28,6 +28,7 @@ export function ComposingSettings() {
     attachmentReminderKeywords,
     subAddressDelimiter,
     signaturePosition,
+    signatureSeparatorEnabled,
     updateSetting,
   } = useSettingsStore();
 
@@ -62,6 +63,13 @@ export function ComposingSettings() {
         />
       </SettingItem>
 
+      <SettingItem label={t('signature_separator.label')} description={t('signature_separator.description')}>
+        <ToggleSwitch
+          checked={signatureSeparatorEnabled}
+          onChange={(checked) => updateSetting('signatureSeparatorEnabled', checked)}
+        />
+      </SettingItem>
+
       <SettingItem
         label={t('sub_address_delimiter.label')}
         description={t('sub_address_delimiter.description', { delimiter: subAddressDelimiter })}

lib/signature-utils.ts

@@ -110,13 +110,18 @@ export function getPlainTextSignature(signature?: SignatureSource | null): strin
   return '';
 }
 
-export function appendPlainTextSignature(body: string, signature?: SignatureSource | null): string {
+export function appendPlainTextSignature(
+  body: string,
+  signature?: SignatureSource | null,
+  options: { separator?: boolean } = {},
+): string {
   const plainTextSignature = getPlainTextSignature(signature);
   if (!plainTextSignature) {
     return body;
   }
 
-  return `${body}\n\n-- \n${plainTextSignature}`;
+  const sep = options.separator === false ? '\n\n' : '\n\n-- \n';
+  return `${body}${sep}${plainTextSignature}`;
 }
 
 export function hasMeaningfulHtmlBody(html: string): boolean {

locales/cs/common.json

@@ -977,6 +977,10 @@
         "above_quote": "Před citovaným textem",
         "below_quote": "Za citovaným textem"
       },
+      "signature_separator": {
+        "label": "Oddělovač podpisu",
+        "description": "Před podpis přidat standardní oddělovací řádek \"-- \" (RFC 3676). Vypněte, pokud chcete plynule přejít z textu zprávy do podpisu."
+      },
       "sub_address_delimiter": {
         "label": "Oddělovač sub-adresy",
         "description": "Znak oddělující uživatelské jméno od sub-adresy. Zvolte oddělovač používaný vaším poštovním serverem (např. uzivatel{delimiter}stitek@domena.cz).",

locales/de/common.json

@@ -977,6 +977,10 @@
         "above_quote": "Vor zitiertem Text",
         "below_quote": "Nach zitiertem Text"
       },
+      "signature_separator": {
+        "label": "Signatur-Trenner",
+        "description": "Der Signatur die Standard-Trennerzeile \"-- \" voranstellen (RFC 3676). Deaktivieren, wenn der Nachrichtentext direkt in die Signatur übergehen soll."
+      },
       "sub_address_delimiter": {
         "label": "Sub-Adress-Trennzeichen",
         "description": "Zeichen, das Ihren Benutzernamen vom Sub-Adress-Tag trennt. Verwenden Sie das von Ihrem Mailserver verwendete Trennzeichen (z. B. benutzer{delimiter}tag@domain.de).",

locales/en/common.json

@@ -980,6 +980,10 @@
         "above_quote": "Before quoted text",
         "below_quote": "After quoted text"
       },
+      "signature_separator": {
+        "label": "Signature Delimiter",
+        "description": "Prefix the signature with the standard \"-- \" delimiter line (RFC 3676). Turn off if you'd rather flow straight from your message into the signature."
+      },
       "sub_address_delimiter": {
         "label": "Sub-Address Delimiter",
         "description": "Character separating your username from a sub-address tag. Match the delimiter your mail server uses (e.g. user{delimiter}tag@domain.com).",

locales/es/common.json

@@ -972,6 +972,10 @@
         "above_quote": "Antes del texto citado",
         "below_quote": "Después del texto citado"
       },
+      "signature_separator": {
+        "label": "Delimitador de firma",
+        "description": "Anteponer a la firma la línea delimitadora estándar \"-- \" (RFC 3676). Desactiva si prefieres pasar directamente del mensaje a la firma."
+      },
       "sub_address_delimiter": {
         "label": "Delimitador de sub-dirección",
         "description": "Carácter que separa tu nombre de usuario de la etiqueta de sub-dirección. Usa el delimitador que utilice tu servidor de correo (por ejemplo, usuario{delimiter}etiqueta@dominio.com).",

locales/fr/common.json

@@ -972,6 +972,10 @@
         "above_quote": "Avant le texte cité",
         "below_quote": "Après le texte cité"
       },
+      "signature_separator": {
+        "label": "Délimiteur de signature",
+        "description": "Préfixer la signature par la ligne de délimitation standard \"-- \" (RFC 3676). Désactivez si vous préférez enchaîner directement du message à la signature."
+      },
       "sub_address_delimiter": {
         "label": "Délimiteur de sous-adresse",
         "description": "Caractère séparant votre nom d'utilisateur de l'étiquette de sous-adresse. Utilisez le délimiteur configuré sur votre serveur de messagerie (par ex. utilisateur{delimiter}tag@domaine.com).",

locales/it/common.json

@@ -972,6 +972,10 @@
         "above_quote": "Prima del testo citato",
         "below_quote": "Dopo il testo citato"
       },
+      "signature_separator": {
+        "label": "Delimitatore firma",
+        "description": "Anteporre alla firma la riga di delimitazione standard \"-- \" (RFC 3676). Disattiva se preferisci passare direttamente dal messaggio alla firma."
+      },
       "sub_address_delimiter": {
         "label": "Delimitatore sub-indirizzo",
         "description": "Carattere che separa il tuo nome utente dall'etichetta del sub-indirizzo. Usa il delimitatore configurato sul tuo server di posta (es. utente{delimiter}tag@dominio.com).",

locales/ja/common.json

@@ -972,6 +972,10 @@
         "above_quote": "引用テキストの前",
         "below_quote": "引用テキストの後"
       },
+      "signature_separator": {
+        "label": "署名区切り",
+        "description": "署名の前に標準の区切り行「-- 」（RFC 3676）を付けます。本文から署名へ直接続けたい場合はオフにしてください。"
+      },
       "sub_address_delimiter": {
         "label": "サブアドレス区切り文字",
         "description": "ユーザー名とサブアドレスタグを区切る文字です。お使いのメールサーバーが使用する区切り文字に合わせてください（例: user{delimiter}tag@domain.com）。",

locales/ko/common.json

@@ -977,6 +977,10 @@
         "above_quote": "인용 텍스트 앞",
         "below_quote": "인용 텍스트 뒤"
       },
+      "signature_separator": {
+        "label": "서명 구분선",
+        "description": "서명 앞에 표준 구분선 \"-- \" (RFC 3676)을 추가합니다. 본문에서 바로 서명으로 이어지길 원하면 해제하세요."
+      },
       "sub_address_delimiter": {
         "label": "서브 주소 구분자",
         "description": "사용자 이름과 서브 주소 태그를 나누는 문자예요. 메일 서버가 사용하는 구분자에 맞춰 주세요 (예: user{delimiter}tag@domain.com).",

locales/lv/common.json

@@ -972,6 +972,10 @@
         "above_quote": "Pirms citētā teksta",
         "below_quote": "Pēc citētā teksta"
       },
+      "signature_separator": {
+        "label": "Paraksta atdalītājs",
+        "description": "Pirms paraksta pievienot standarta atdalītāju \"-- \" (RFC 3676). Izslēdziet, ja vēlaties pāriet no ziņojuma tieši uz parakstu."
+      },
       "sub_address_delimiter": {
         "label": "Apakšadreses atdalītājs",
         "description": "Zīme, kas atdala lietotājvārdu no apakšadreses tagu. Izvēlieties atdalītāju, ko lieto jūsu pasta serveris (piem. lietotajs{delimiter}tags@domens.lv).",

locales/nl/common.json

@@ -972,6 +972,10 @@
         "above_quote": "Voor geciteerde tekst",
         "below_quote": "Na geciteerde tekst"
       },
+      "signature_separator": {
+        "label": "Handtekening-scheider",
+        "description": "De handtekening voorafgaan met de standaard scheidingsregel \"-- \" (RFC 3676). Zet uit als je liever direct van het bericht in de handtekening overgaat."
+      },
       "sub_address_delimiter": {
         "label": "Sub-adres scheidingsteken",
         "description": "Teken dat je gebruikersnaam scheidt van het sub-adres-label. Gebruik het scheidingsteken dat je mailserver gebruikt (bv. gebruiker{delimiter}tag@domein.nl).",

locales/pl/common.json

@@ -977,6 +977,10 @@
         "above_quote": "Przed cytowanym tekstem",
         "below_quote": "Po cytowanym tekście"
       },
+      "signature_separator": {
+        "label": "Separator podpisu",
+        "description": "Poprzedź podpis standardową linią separatora \"-- \" (RFC 3676). Wyłącz, jeśli chcesz przejść bezpośrednio z treści wiadomości do podpisu."
+      },
       "sub_address_delimiter": {
         "label": "Separator sub-adresu",
         "description": "Znak oddzielający Twoją nazwę użytkownika od tagu sub-adresu. Użyj separatora zgodnego z Twoim serwerem pocztowym (np. user{delimiter}tag@domain.com).",

locales/pt/common.json

@@ -972,6 +972,10 @@
         "above_quote": "Antes do texto citado",
         "below_quote": "Depois do texto citado"
       },
+      "signature_separator": {
+        "label": "Delimitador de assinatura",
+        "description": "Anteceder a assinatura com a linha delimitadora padrão \"-- \" (RFC 3676). Desative se preferir passar direto da mensagem para a assinatura."
+      },
       "sub_address_delimiter": {
         "label": "Delimitador de sub-endereço",
         "description": "Caractere que separa seu nome de usuário da tag de sub-endereço. Use o delimitador configurado no seu servidor de e-mail (ex.: usuario{delimiter}tag@dominio.com).",

locales/ru/common.json

@@ -972,6 +972,10 @@
         "above_quote": "Перед цитируемым текстом",
         "below_quote": "После цитируемого текста"
       },
+      "signature_separator": {
+        "label": "Разделитель подписи",
+        "description": "Добавлять перед подписью стандартную строку-разделитель \"-- \" (RFC 3676). Отключите, если хотите переходить от текста сразу к подписи."
+      },
       "sub_address_delimiter": {
         "label": "Разделитель суб-адресов",
         "description": "Символ, отделяющий имя пользователя от тега суб-адреса. Используйте разделитель, настроенный на вашем почтовом сервере (например, user{delimiter}tag@domain.com).",

locales/tr/common.json

@@ -977,6 +977,10 @@
         "above_quote": "Alıntılanan metinden önce",
         "below_quote": "Alıntılanan metinden sonra"
       },
+      "signature_separator": {
+        "label": "İmza ayırıcı",
+        "description": "İmzayı standart \"-- \" ayırıcı satırıyla başlat (RFC 3676). Mesajdan doğrudan imzaya geçmek istiyorsanız kapatın."
+      },
       "sub_address_delimiter": {
         "label": "Alt Adres Ayırıcı",
         "description": "Kullanıcı adını alt adres etiketinden ayıran karakter. Posta sunucunuzun kullandığı ayırıcıyı seçin (ör. kullanici{delimiter}etiket@domain.com).",

locales/uk/common.json

@@ -977,6 +977,10 @@
         "above_quote": "Перед цитованим текстом",
         "below_quote": "Після цитованого тексту"
       },
+      "signature_separator": {
+        "label": "Розділювач підпису",
+        "description": "Додавати перед підписом стандартний рядок-розділювач \"-- \" (RFC 3676). Вимкніть, якщо хочете переходити з повідомлення відразу до підпису."
+      },
       "sub_address_delimiter": {
         "label": "Розділювач під-адреси",
         "description": "Символ, який відокремлює ім'я користувача від мітки під-адреси. Використовуйте розділювач, налаштований на вашому поштовому сервері (напр. user{delimiter}tag@domain.com).",

locales/zh/common.json

@@ -977,6 +977,10 @@
         "above_quote": "引用文本之前",
         "below_quote": "引用文本之后"
       },
+      "signature_separator": {
+        "label": "签名分隔符",
+        "description": "在签名前加入标准的 “-- ” 分隔行（RFC 3676）。如果希望正文直接连到签名，请关闭。"
+      },
       "sub_address_delimiter": {
         "label": "子地址分隔符",
         "description": "用于分隔用户名和子地址标签的字符。请选择与您的邮件服务器一致的分隔符（例如 user{delimiter}tag@domain.com）。",

stores/settings-store.ts

@@ -145,6 +145,7 @@ interface SettingsState {
   plainTextMode: boolean; // Send plain text only (no rich text editor)
   subAddressDelimiter: string; // Character separating user from tag (e.g. "user+tag@")
   signaturePosition: SignaturePosition; // Position of the signature relative to quoted text in replies/forwards
+  signatureSeparatorEnabled: boolean; // Prefix the signature with the RFC 3676 "-- " delimiter
 
   // Privacy & Security
   sessionTimeout: number; // minutes (0 = never)
@@ -298,6 +299,7 @@ const DEFAULT_SETTINGS = {
   plainTextMode: false,
   subAddressDelimiter: DEFAULT_SUB_ADDRESS_DELIMITER,
   signaturePosition: 'below_quote' as SignaturePosition,
+  signatureSeparatorEnabled: true,
 
   // Privacy & Security
   sessionTimeout: 0, // Never
@@ -470,6 +472,7 @@ export const useSettingsStore = create<SettingsState>()(
           plainTextMode: state.plainTextMode,
           subAddressDelimiter: state.subAddressDelimiter,
           signaturePosition: state.signaturePosition,
+          signatureSeparatorEnabled: state.signatureSeparatorEnabled,
           sessionTimeout: state.sessionTimeout,
           emailNotificationsEnabled: state.emailNotificationsEnabled,
           emailNotificationSound: state.emailNotificationSound,