diff --git a/openless-all/app/src-tauri/src/commands.rs b/openless-all/app/src-tauri/src/commands.rs
index 19b8e02e..54f4a194 100644
--- a/openless-all/app/src-tauri/src/commands.rs
+++ b/openless-all/app/src-tauri/src/commands.rs
@@ -200,7 +200,7 @@ fn emit_prefs_changed(app: &AppHandle, prefs: &UserPreferences) {
     let _ = app.emit_to("main", "prefs:changed", prefs);
 }
 
-fn sync_style_pack_prefs_and_persist(
+pub(crate) fn sync_style_pack_prefs_and_persist(
     coord: &Coordinator,
     app: &AppHandle,
     mut prefs: UserPreferences,
@@ -216,6 +216,54 @@ fn sync_style_pack_prefs_and_persist(
     Ok(prefs)
 }
 
+pub(crate) fn activate_style_pack_by_id(
+    coord: &Coordinator,
+    app: &AppHandle,
+    id: &str,
+) -> Result<StylePack, String> {
+    let mut prefs = coord.prefs().get();
+    let pack = coord.style_packs().get(id).map_err(|e| e.to_string())?;
+    log::info!(
+        "[style-pack] activate helper requested id={} kind={:?} base_mode={:?} enabled={}",
+        pack.id,
+        pack.kind,
+        pack.base_mode,
+        pack.enabled
+    );
+    if !pack.enabled {
+        coord
+            .style_packs()
+            .set_enabled(id, true)
+            .map_err(|e| e.to_string())?;
+    }
+    prefs.active_style_pack_id = id.to_string();
+    sync_style_pack_prefs_and_persist(coord, app, prefs)?;
+    log::info!("[style-pack] activate helper applied id={id}");
+    coord
+        .style_packs()
+        .get(id)
+        .map(|mut pack| {
+            pack.active = true;
+            pack
+        })
+        .map_err(|e| e.to_string())
+}
+
+pub(crate) fn activate_builtin_style_mode(
+    coord: &Coordinator,
+    app: &AppHandle,
+    mode: PolishMode,
+) -> Result<(), String> {
+    let pack_id = builtin_style_pack_id(mode).to_string();
+    log::info!(
+        "[style-pack] activate builtin mode helper mode={:?} pack_id={}",
+        mode,
+        pack_id
+    );
+    let _ = activate_style_pack_by_id(coord, app, &pack_id)?;
+    Ok(())
+}
+
 // ─────────────────────────── release channel (Beta opt-in) ───────────────────────────
 //
 // 渠道偏好的写入路径跟 set_settings 复用 persist_settings：保持热键兜底归一化
@@ -1243,32 +1291,7 @@ pub fn set_active_style_pack(
     app: AppHandle,
     id: String,
 ) -> Result<StylePack, String> {
-    let mut prefs = coord.prefs().get();
-    let pack = coord.style_packs().get(&id).map_err(|e| e.to_string())?;
-    log::info!(
-        "[style-pack] command activate requested id={} kind={:?} base_mode={:?} enabled={}",
-        pack.id,
-        pack.kind,
-        pack.base_mode,
-        pack.enabled
-    );
-    if !pack.enabled {
-        coord
-            .style_packs()
-            .set_enabled(&id, true)
-            .map_err(|e| e.to_string())?;
-    }
-    prefs.active_style_pack_id = id.clone();
-    sync_style_pack_prefs_and_persist(&*coord, &app, prefs)?;
-    log::info!("[style-pack] command activate applied id={id}");
-    coord
-        .style_packs()
-        .get(&id)
-        .map(|mut pack| {
-            pack.active = true;
-            pack
-        })
-        .map_err(|e| e.to_string())
+    activate_style_pack_by_id(&coord, &app, &id)
 }
 
 #[tauri::command]
@@ -1369,20 +1392,7 @@ pub fn set_default_polish_mode(
     app: AppHandle,
     mode: PolishMode,
 ) -> Result<(), String> {
-    let mut prefs = coord.prefs().get();
-    let pack_id = builtin_style_pack_id(mode).to_string();
-    log::info!(
-        "[style-pack] compat set_default_polish_mode mode={:?} pack_id={}",
-        mode,
-        pack_id
-    );
-    coord
-        .style_packs()
-        .set_enabled(&pack_id, true)
-        .map_err(|e| e.to_string())?;
-    prefs.active_style_pack_id = pack_id;
-    let _ = sync_style_pack_prefs_and_persist(&*coord, &app, prefs)?;
-    Ok(())
+    activate_builtin_style_mode(&coord, &app, mode)
 }
 
 #[tauri::command]
diff --git a/openless-all/app/src-tauri/src/coordinator/dictation.rs b/openless-all/app/src-tauri/src/coordinator/dictation.rs
index 1a8f770b..4376be9a 100644
--- a/openless-all/app/src-tauri/src/coordinator/dictation.rs
+++ b/openless-all/app/src-tauri/src/coordinator/dictation.rs
@@ -273,6 +273,44 @@ async fn run_streaming_polish(
     }
 }
 
+fn finalize_polished_text(
+    polished: String,
+    translation_active: bool,
+    raw_uses_llm: bool,
+    mode: PolishMode,
+    polish_error: &Option<String>,
+    chinese_script_preference: crate::types::ChineseScriptPreference,
+    correction_rules: &[crate::types::CorrectionRule],
+    already_streamed: bool,
+) -> String {
+    if already_streamed {
+        return polished;
+    }
+    let should_force_script = if translation_active {
+        polish_error.is_some()
+    } else {
+        (!raw_uses_llm && mode == PolishMode::Raw) || polish_error.is_some()
+    };
+    let polished = if should_force_script {
+        apply_chinese_script_preference(&polished, chinese_script_preference)
+    } else {
+        polished
+    };
+    if correction_rules.is_empty() {
+        polished
+    } else {
+        let corrected = apply_correction_rules(&polished, correction_rules);
+        if corrected != polished {
+            log::info!(
+                "[coord] correction rules adjusted final text ({} → {} chars)",
+                polished.chars().count(),
+                corrected.chars().count()
+            );
+        }
+        corrected
+    }
+}
+
 pub(super) async fn handle_pressed_edge(inner: &Arc<Inner>) {
     let was_held = inner.hotkey_trigger_held.swap(true, Ordering::SeqCst);
     if !was_held {
@@ -1334,32 +1372,16 @@ pub(super) async fn end_session(inner: &Arc<Inner>) -> Result<(), String> {
         (p, e, false)
     };
 
-    // 仅在“ASR 直出文本”场景做强制简繁收敛，避免误伤成功的翻译/常规 LLM 输出：
-    // - 非翻译模式：mode=Raw（本来就不走润色）或润色失败回退 raw
-    // - 翻译模式：仅翻译失败回退 raw 时才收敛
-    let should_force_script = if translation_active {
-        polish_error.is_some()
-    } else {
-        (!raw_uses_llm && mode == PolishMode::Raw) || polish_error.is_some()
-    };
-    let polished = if should_force_script {
-        apply_chinese_script_preference(&polished, chinese_script_preference)
-    } else {
-        polished
-    };
-    let polished = if correction_rules.is_empty() {
-        polished
-    } else {
-        let corrected = apply_correction_rules(&polished, &correction_rules);
-        if corrected != polished {
-            log::info!(
-                "[coord] correction rules adjusted final text ({} → {} chars)",
-                polished.chars().count(),
-                corrected.chars().count()
-            );
-        }
-        corrected
-    };
+    let polished = finalize_polished_text(
+        polished,
+        translation_active,
+        raw_uses_llm,
+        mode,
+        &polish_error,
+        chinese_script_preference,
+        &correction_rules,
+        already_streamed,
+    );
     // 原子化最后一次 cancel 检查 + 转 Inserting：
     // 在同一 lock 内决定「丢弃」还是「进入 Inserting」。一旦设到 Inserting，
     // cancel_session 就拒绝介入（Cmd+V 已发出，撤销不掉）。这是 audit HIGH #2 的修复，
@@ -1570,3 +1592,55 @@ pub(super) fn cancel_session(inner: &Arc<Inner>) {
     log::info!("[coord] session cancelled (was {:?})", decision.phase);
     schedule_capsule_idle(inner, CAPSULE_AUTO_HIDE_DELAY_MS);
 }
+
+#[cfg(test)]
+mod tests {
+    use super::finalize_polished_text;
+    use crate::types::{ChineseScriptPreference, CorrectionRule, PolishMode};
+
+    fn correction_rule(pattern: &str, replacement: &str) -> CorrectionRule {
+        CorrectionRule {
+            id: "test".into(),
+            pattern: pattern.into(),
+            replacement: replacement.into(),
+            enabled: true,
+            created_at: String::new(),
+        }
+    }
+
+    #[test]
+    fn streamed_output_skips_postprocessing_mutations() {
+        let rules = vec![correction_rule("Open AI", "OpenAI")];
+
+        let result = finalize_polished_text(
+            "Open AI".into(),
+            false,
+            false,
+            PolishMode::Raw,
+            &None,
+            ChineseScriptPreference::Auto,
+            &rules,
+            true,
+        );
+
+        assert_eq!(result, "Open AI");
+    }
+
+    #[test]
+    fn non_streamed_output_still_applies_correction_rules() {
+        let rules = vec![correction_rule("Open AI", "OpenAI")];
+
+        let result = finalize_polished_text(
+            "Open AI".into(),
+            false,
+            false,
+            PolishMode::Raw,
+            &None,
+            ChineseScriptPreference::Auto,
+            &rules,
+            false,
+        );
+
+        assert_eq!(result, "OpenAI");
+    }
+}
diff --git a/openless-all/app/src-tauri/src/lib.rs b/openless-all/app/src-tauri/src/lib.rs
index 53749b38..420c4ba8 100644
--- a/openless-all/app/src-tauri/src/lib.rs
+++ b/openless-all/app/src-tauri/src/lib.rs
@@ -476,7 +476,12 @@ fn build_style_tray_menu<M: Manager<tauri::Wry>>(
     app: &M,
     coordinator: &Arc<coordinator::Coordinator>,
 ) -> tauri::Result<StyleTrayMenu> {
-    let selected = coordinator.prefs().get().default_mode;
+    let prefs = coordinator.prefs().get();
+    let selected = coordinator
+        .style_packs()
+        .get_or_default_active(&prefs.active_style_pack_id)
+        .map(|pack| pack.base_mode)
+        .unwrap_or(prefs.default_mode);
     let mut submenu = SubmenuBuilder::with_id(app, "style", "输出风格");
     for entry in tray_polish_mode_menu_entries(selected) {
         let item = CheckMenuItemBuilder::with_id(&entry.id, entry.label)
@@ -630,14 +635,10 @@ fn handle_style_tray_menu_event(app: &AppHandle, id: &str) -> bool {
         return false;
     };
     let coord = app.state::<Arc<coordinator::Coordinator>>();
-    let mut prefs = coord.prefs().get();
-    prefs.default_mode = mode;
-    if let Err(err) = coord.prefs().set(prefs.clone()) {
-        log::warn!("[tray] save polish mode preference failed: {err}");
+    if let Err(err) = commands::activate_builtin_style_mode(&coord, app, mode) {
+        log::warn!("[tray] activate builtin style mode failed: {err}");
         return true;
     }
-    let _ = app.emit("prefs:changed", &prefs);
-    let _ = app.emit_to("main", "prefs:changed", &prefs);
     if let Err(err) = refresh_tray_microphone_menu(app) {
         log::warn!("[tray] refresh style menu after polish mode change failed: {err}");
     }
diff --git a/openless-all/app/src-tauri/src/persistence.rs b/openless-all/app/src-tauri/src/persistence.rs
index 1041173b..4e5db7e3 100644
--- a/openless-all/app/src-tauri/src/persistence.rs
+++ b/openless-all/app/src-tauri/src/persistence.rs
@@ -1012,7 +1012,7 @@ impl StylePackStore {
         }
         if let Some(pack) = packs
             .iter()
-            .find(|pack| pack.id == BUILTIN_STYLE_PACK_LIGHT_ID)
+            .find(|pack| pack.id == BUILTIN_STYLE_PACK_LIGHT_ID && pack.enabled)
             .cloned()
         {
             return Ok(pack);
diff --git a/openless-all/app/src-tauri/src/types.rs b/openless-all/app/src-tauri/src/types.rs
index d07f1f02..187fcb41 100644
--- a/openless-all/app/src-tauri/src/types.rs
+++ b/openless-all/app/src-tauri/src/types.rs
@@ -195,6 +195,7 @@ impl StyleSystemPrompts {
     }
 
     pub fn with_legacy_custom_prompts(mut self, legacy: &CustomStylePrompts) -> Self {
+        const LEGACY_CUSTOM_PROMPT_MARKER: &str = "\n\n# 用户自定义附加要求\n";
         for mode in [
             PolishMode::Raw,
             PolishMode::Light,
@@ -205,6 +206,9 @@ impl StyleSystemPrompts {
             if legacy_prompt.is_empty() {
                 continue;
             }
+            if self.for_mode(mode).contains(LEGACY_CUSTOM_PROMPT_MARKER) {
+                continue;
+            }
             let merged = format!(
                 "{}\n\n# 用户自定义附加要求\n{}",
                 self.for_mode(mode).trim_end(),
@@ -1594,6 +1598,21 @@ mod tests {
         assert!(prefs.custom_style_prompts.has_for_mode(PolishMode::Formal));
     }
 
+    #[test]
+    fn legacy_custom_style_prompts_are_not_appended_twice() {
+        let base = StyleSystemPrompts::default();
+        let legacy = CustomStylePrompts {
+            light: "更像微信消息".into(),
+            ..CustomStylePrompts::default()
+        };
+
+        let once = base.clone().with_legacy_custom_prompts(&legacy);
+        let twice = once.clone().with_legacy_custom_prompts(&legacy);
+
+        assert_eq!(once.light, twice.light);
+        assert_eq!(twice.light.matches("# 用户自定义附加要求").count(), 1);
+    }
+
     /// issue #360: 默认值必须是 CtrlV，跟历史行为一致；老配置文件没有
     /// pasteShortcut 字段时反序列化也得回到 CtrlV，否则会把现有用户的粘贴
     /// 行为静默改掉。