GCWing · bobleer · Aug 6, 2026 · Aug 6, 2026
diff --git a/src/apps/desktop/src/api/miniapp_export_api.rs b/src/apps/desktop/src/api/miniapp_export_api.rs
@@ -19,6 +19,7 @@ const RENDER_TIMEOUT_MS: u64 = 30_000;
 const RENDER_SETTLE_MS: u64 = 900;
 /// Reused hidden host — one window, navigate per slide (avoids create/close flash per page).
 const EXPORT_HOST_LABEL: &str = "miniapp-slide-export-host";
+const UTF8_BOM: &[u8] = b"\xEF\xBB\xBF";
 
 #[derive(Debug, Deserialize)]
 #[serde(rename_all = "camelCase")]
@@ -41,6 +42,13 @@ fn wrap_slide_html(html: &str, width: u32, height: u32) -> String {
     )
 }
 
+fn utf8_html_bytes(html: &str) -> Vec<u8> {
+    let mut bytes = Vec::with_capacity(UTF8_BOM.len() + html.len());
+    bytes.extend_from_slice(UTF8_BOM);
+    bytes.extend_from_slice(html.as_bytes());
+    bytes
+}
+
 /// Write slide HTML to app cache and return a `file://` URL for the export webview.
 fn file_url_for_export_html<R: tauri::Runtime>(
     app: &AppHandle<R>,
@@ -54,7 +62,10 @@ fn file_url_for_export_html<R: tauri::Runtime>(
     std::fs::create_dir_all(&export_dir)
         .map_err(|error| format!("Failed to create export cache dir: {error}"))?;
     let file_path = export_dir.join(format!("slide-{}.html", Uuid::new_v4()));
-    std::fs::write(&file_path, html)
+    // Sanitized slide documents may intentionally omit author-provided meta
+    // tags. The BOM makes the file encoding unambiguous before a hidden
+    // WebView renders it to PDF or PNG.
+    std::fs::write(&file_path, utf8_html_bytes(html))
         .map_err(|error| format!("Failed to write export HTML: {error}"))?;
     let url = tauri::Url::from_file_path(&file_path)
         .map_err(|_| "Failed to build file URL for export webview".to_string())?;
@@ -164,3 +175,31 @@ pub async fn miniapp_render_slide_page(
         other => Err(format!("Unsupported slide render format: {other}")),
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::{utf8_html_bytes, wrap_slide_html, UTF8_BOM};
+
+    #[test]
+    fn export_html_bytes_are_utf8_even_when_full_document_has_no_charset_meta() {
+        let document = wrap_slide_html(
+            "<!doctype html><html><head><title>架构说明</title></head><body>中文 · café</body></html>",
+            1280,
+            720,
+        );
+        assert!(!document.to_ascii_lowercase().contains("charset="));
+
+        let bytes = utf8_html_bytes(&document);
+        assert!(bytes.starts_with(UTF8_BOM));
+        assert_eq!(
+            std::str::from_utf8(&bytes[UTF8_BOM.len()..]).expect("HTML should remain valid UTF-8"),
+            document
+        );
+    }
+
+    #[test]
+    fn fragment_wrapper_keeps_its_explicit_utf8_charset() {
+        let document = wrap_slide_html("<main>中文</main>", 1280, 720);
+        assert!(document.contains("<meta charset=\"UTF-8\">"));
+    }
+}
diff --git a/src/crates/contracts/product-domains/src/miniapp/builtin.rs b/src/crates/contracts/product-domains/src/miniapp/builtin.rs
@@ -151,7 +151,7 @@ pub const BUILTIN_APPS: &[BuiltinMiniAppBundle] = &[
     },
     BuiltinMiniAppBundle {
         id: "builtin-ppt-live",
-        version: 258,
+        version: 259,
         meta_json: include_str!("builtin/assets/ppt-live/meta.json"),
         html: include_str!("builtin/assets/ppt-live/index.html"),
         css: include_str!("builtin/assets/ppt-live/style.css"),
@@ -549,9 +549,9 @@ mod tests {
         assert_eq!(meta["version"].as_u64(), Some(u64::from(app.version)));
         assert_eq!(bundle["version"].as_u64(), Some(u64::from(app.version)));
         assert_eq!(meta["permissions"]["node"]["enabled"], false);
-        // AI permission is enabled so the UI can list models for Cowork selection
-        // via app.ai.getModels(); generation still goes through agent.run.
-        assert_eq!(meta["permissions"]["ai"]["enabled"], true);
+        // Model selection belongs to the host's shared ChatInput; PPT Live no
+        // longer needs raw AI access merely to duplicate the model catalog.
+        assert!(meta["permissions"].get("ai").is_none());
         assert_eq!(meta["permissions"]["agent"]["enabled"], true);
         assert_eq!(meta["permissions"]["agent"]["rate_limit_per_minute"], 120);
         // Research happens inside hidden agent turns (WebSearch/WebFetch via
@@ -585,7 +585,7 @@ mod tests {
         // reads the files back instead of parsing giant JSON text.
         assert!(adapter_source.contains("protocol: 'files'"));
         assert!(adapter_source.contains("appDataWorkspace: options.appDataWorkspace"));
-        assert!(adapter_source.contains("model: options.model"));
+        assert!(!adapter_source.contains("model: options.model"));
         assert!(adapter_source.contains("displayText: options.displayText"));
         assert!(app.ui_js.contains("payload?.displayText"));
         assert!(app
@@ -596,8 +596,9 @@ mod tests {
         let ui_source = include_str!("builtin/assets/ppt-live/ui.js");
         assert!(ui_source.contains("backendUsesFileProtocol"));
         assert!(ui_source.contains("tryReadDeckSlideFile"));
-        assert!(ui_source.contains("preferredModel"));
-        assert!(ui_source.contains("modelSelect"));
+        assert!(!ui_source.contains("preferredModel"));
+        assert!(!ui_source.contains("modelSelect"));
+        assert!(!app.html.contains("modelSelect"));
         assert!(meta["permissions"]["fs"]["read"]
             .as_array()
             .is_some_and(|scopes| scopes.iter().any(|scope| scope == "{appdata}")));
@@ -608,9 +609,6 @@ mod tests {
         assert!(
             include_str!("builtin/assets/ppt-live/ui.js").contains("installBitFunBackendAdapter")
         );
-        assert!(meta["permissions"]["ai"]["enabled"]
-            .as_bool()
-            .unwrap_or(false));
         // The single cowork agent turn loads the stable ppt-design skill key.
         assert!(prompt_source.contains("user::bitfun-system::ppt-design"));
         let ppt_live_source = include_str!("builtin/assets/ppt-live/ui.js");

diff --git a/src/crates/contracts/product-domains/src/miniapp/builtin/assets/ppt-live/bundle.json b/src/crates/contracts/product-domains/src/miniapp/builtin/assets/ppt-live/bundle.json
@@ -1,5 +1,5 @@
 {
   "schemaVersion": 1,
   "id": "builtin-ppt-live",
-  "version": 258
+  "version": 259
 }
diff --git a/src/crates/contracts/product-domains/src/miniapp/builtin/assets/ppt-live/dist/ui.bundle.js b/src/crates/contracts/product-domains/src/miniapp/builtin/assets/ppt-live/dist/ui.bundle.js
@@ -7031,10 +7031,6 @@ var STRINGS = {
     propertiesFont: "Font",
     propertiesColorMode: "Slide colors",
     propertiesStylePreset: "Style preset",
-    propertiesModel: "Model",
-    modelOptionAuto: "Auto (host default)",
-    modelOptionPrimary: "Primary",
-    modelOptionFast: "Fast",
     colorModeLight: "Light",
     colorModeDark: "Dark",
     fontSansSerif: "Sans-serif",
@@ -7443,10 +7439,6 @@ var STRINGS = {
     propertiesFont: "\u5B57\u4F53",
     propertiesColorMode: "\u5E7B\u706F\u7247\u914D\u8272",
     propertiesStylePreset: "\u98CE\u683C\u9884\u8BBE",
-    propertiesModel: "\u6A21\u578B",
-    modelOptionAuto: "\u81EA\u52A8\uFF08\u8DDF\u968F\u4E3B\u673A\u9ED8\u8BA4\uFF09",
-    modelOptionPrimary: "\u4E3B\u6A21\u578B",
-    modelOptionFast: "\u5FEB\u901F\u6A21\u578B",
     colorModeLight: "\u6D45\u8272",
     colorModeDark: "\u6DF1\u8272",
     fontSansSerif: "\u975E\u886C\u7EBF",
@@ -7743,12 +7735,7 @@ function getAllStylePresets(locale) {
 // src/state.js
 var STORAGE_KEY = "pptLiveStudioStateV6";
 var HISTORY_KEY = "pptLiveDeckHistoryV1";
-var SCHEMA_VERSION = 6;
-var DEFAULT_PREFERRED_MODEL = "primary";
-function normalizePreferredModel(value) {
-  const raw = String(value || "").trim();
-  return raw || DEFAULT_PREFERRED_MODEL;
-}
+var SCHEMA_VERSION = 7;
 var ELEMENT_TYPES = ["text", "list", "shape", "metric", "chart", "media"];
 var THEME_PRESETS = {
   executive: {
@@ -7906,7 +7893,6 @@ function createInitialState() {
       runId: "",
       skillKey: ""
     },
-    preferredModel: DEFAULT_PREFERRED_MODEL,
     style: defaultStyle(),
     outline: [],
     sources: { items: [], facts: [], warnings: [], summary: "", fetchedAt: 0 },
@@ -7947,7 +7933,7 @@ function ensureState(value) {
     runId: String(state2.agentSession?.runId || ""),
     skillKey: String(state2.agentSession?.skillKey || "")
   };
-  state2.preferredModel = normalizePreferredModel(state2.preferredModel);
+  delete state2.preferredModel;
   state2.style = { ...defaultStyle(), ...state2.style || {} };
   delete state2.style.brandPrimary;
   delete state2.style.brandAccent;
@@ -37466,8 +37452,7 @@ function installAgentBackend(app) {
       return app.agent.ensureSession({
         sessionName: "PPT Live",
         sessionId: options.sessionId,
-        appDataWorkspace: options.appDataWorkspace,
-        model: options.model || void 0
+        appDataWorkspace: options.appDataWorkspace
       });
     },
     async call(action, input, options = {}) {
@@ -37480,8 +37465,7 @@ function installAgentBackend(app) {
         sessionName: "PPT Live",
         displayText: options.displayText || input.instruction,
         sessionId: options.sessionId,
-        appDataWorkspace: options.appDataWorkspace,
-        model: options.model || void 0
+        appDataWorkspace: options.appDataWorkspace
       });
       if (!result?.sessionId || !result?.turnId) {
         throw new Error("PPT Live agent backend did not return sessionId/turnId");
@@ -38745,8 +38729,7 @@ async function ensureDeckAgentSession() {
   const project = currentDeckProject() || newDeckProject();
   const requestSession = async (sessionId2) => host.backend.ensureSession({
     sessionId: sessionId2 || void 0,
-    appDataWorkspace: project.workspaceSubdir,
-    model: normalizePreferredModel(state.preferredModel)
+    appDataWorkspace: project.workspaceSubdir
   });
   let result;
   const persistedSessionId = String(state.agentSession?.id || "");
@@ -38982,15 +38965,11 @@ async function executeBackendTurn(requestInput, hooks = {}, options = {}) {
   const progressTracker = createGenerationProgressTracker();
   const activity = { lastEventAt: Date.now() };
   try {
-    const preferredModel = normalizePreferredModel(
-      options.model || state.preferredModel || DEFAULT_PREFERRED_MODEL
-    );
     const result = await host.backend.call("ppt.generate", requestInput, {
       entityId: "deck",
       idempotencyKey: `ppt-live-${Date.now()}-${Math.random().toString(36).slice(2, 8)}`,
       sessionId: options.sessionId || void 0,
       appDataWorkspace: options.appDataWorkspace || void 0,
-      model: preferredModel,
       displayText: options.displayText || requestInput.instruction
     });
     sessionId = result?.sessionId || null;
@@ -39477,7 +39456,6 @@ async function runCoworkDeckGeneration(operation, instruction, options = {}) {
           runId: retrySession?.project?.runId || "",
           skillKey: PPT_DESIGN_SKILL_KEY
         };
-        state.preferredModel = normalizePreferredModel(state.preferredModel);
         addGenerationEvent({ title: translate("generationParsingDeck"), detail: "", kind: "parsing" });
         setGenerationStep("verify", "running", translate("generationVerifyingDeck"));
         await progressivePublishChain.catch(() => {
@@ -40827,24 +40805,6 @@ function bindPropertyPanels() {
       refreshFlatSelect(stylePresetSelect);
     });
   }
-  const modelSelect = $("modelSelect");
-  if (modelSelect) {
-    enhanceFlatSelect(modelSelect);
-    modelSelect.addEventListener("change", () => {
-      const selected = normalizePreferredModel(modelSelect.value);
-      if (selected === state.preferredModel) return;
-      state.preferredModel = selected;
-      refreshFlatSelect(modelSelect);
-      void (async () => {
-        await ensureDeckAgentSession();
-        await persist(true);
-      })().catch((error2) => {
-        runtime().log?.warn?.("PPT Live failed to prepare the updated model session", {
-          error: String(error2)
-        });
-      });
-    });
-  }
 }
 var exportPreviewIndex = 0;
 function getSelectedExportFormat() {
@@ -41124,58 +41084,10 @@ function renderStylePresetOptions() {
   if (stylePresetSelect.selectedIndex < 0) stylePresetSelect.value = DEFAULT_STYLE_PRESET;
   refreshFlatSelect(stylePresetSelect);
 }
-function appendModelOption(select, value, label) {
-  const option = document.createElement("option");
-  option.value = value;
-  option.textContent = label;
-  select.append(option);
-}
-function modelOptionLabel(model) {
-  const modelName = String(model?.modelName || model?.model_name || "").trim();
-  if (modelName) return modelName;
-  const configName = String(model?.name || "").trim();
-  if (configName) return configName;
-  return String(model?.id || "").trim();
-}
-function renderModelOptions(models = []) {
-  const modelSelect = $("modelSelect");
-  if (!modelSelect) return;
-  const selected = normalizePreferredModel(state.preferredModel);
-  modelSelect.textContent = "";
-  appendModelOption(modelSelect, "auto", translate("modelOptionAuto"));
-  appendModelOption(modelSelect, "primary", translate("modelOptionPrimary"));
-  appendModelOption(modelSelect, "fast", translate("modelOptionFast"));
-  for (const model of Array.isArray(models) ? models : []) {
-    const id = String(model?.id || "").trim();
-    if (!id || id === "auto" || id === "primary" || id === "fast") continue;
-    appendModelOption(modelSelect, id, modelOptionLabel(model));
-  }
-  if (![...modelSelect.options].some((option) => option.value === selected)) {
-    appendModelOption(modelSelect, selected, selected);
-  }
-  modelSelect.value = selected;
-  if (modelSelect.selectedIndex < 0) modelSelect.value = DEFAULT_PREFERRED_MODEL;
-  state.preferredModel = normalizePreferredModel(modelSelect.value);
-  refreshFlatSelect(modelSelect);
-}
-async function loadModelOptions() {
-  renderModelOptions([]);
-  const getModels = runtime()?.ai?.getModels;
-  if (typeof getModels !== "function") return;
-  try {
-    const models = await getModels();
-    renderModelOptions(models);
-  } catch (error2) {
-    runtime().log?.warn?.("PPT Live failed to list AI models", { error: String(error2) });
-    renderModelOptions([]);
-  }
-}
 function syncLocale() {
   state.generation = normalizeGeneration(state.generation);
   applyI18n();
   renderStylePresetOptions();
-  renderModelOptions([]);
-  void loadModelOptions();
   syncComposerClaim();
   rerender();
 }
@@ -41207,7 +41119,6 @@ async function init() {
     syncLocale();
     await ensureDeckAgentSession();
     syncStylePanelFromState(state);
-    await loadModelOptions();
     await persist(true);
   } catch (error2) {
     runtime().log?.error?.("PPT Live init failed", { error: String(error2) });

diff --git a/src/crates/contracts/product-domains/src/miniapp/builtin/assets/ppt-live/index.html b/src/crates/contracts/product-domains/src/miniapp/builtin/assets/ppt-live/index.html
@@ -111,10 +111,6 @@ <h1 data-i18n="title">PPT Live</h1>
                   <button type="button" class="font-toggle__btn" data-color-mode="dark" data-i18n="colorModeDark">Dark</button>
                 </div>
               </div>
-              <div class="property-row is-stack">
-                <span class="property-label" data-i18n="propertiesModel">Model</span>
-                <select id="modelSelect" data-i18n-aria="propertiesModel"></select>
-              </div>
             </div>
           </div>
 

diff --git a/src/crates/contracts/product-domains/src/miniapp/builtin/assets/ppt-live/meta.json b/src/crates/contracts/product-domains/src/miniapp/builtin/assets/ppt-live/meta.json
@@ -10,7 +10,7 @@
     "ppt",
     "ai"
   ],
-  "version": 258,
+  "version": 259,
   "created_at": 0,
   "updated_at": 0,
   "permissions": {
@@ -31,18 +31,12 @@
     "node": {
       "enabled": false
     },
-    "ai": {
-      "enabled": true,
-      "allowed_models": [],
-      "max_tokens_per_request": 16000,
-      "rate_limit_per_minute": 0
-    },
     "agent": {
       "enabled": true,
       "rate_limit_per_minute": 120
     }
   },
-  "permission_rationale": "PPT Live stores only its own deck draft, lists available AI models so the user can choose which Cowork model generates decks, fetches user-provided URLs only when generating source-grounded decks, runs hidden BitFun agent turns (ppt-design skill plus research tools such as WebSearch/WebFetch) only when the user asks it to generate or refine content, and exports PPTX/PDF/PNG/HTML entirely inside the desktop WebView.",
+  "permission_rationale": "PPT Live stores only its own deck draft, runs hidden BitFun agent turns (ppt-design skill plus research tools such as WebSearch/WebFetch) only when the user asks it to generate or refine content, uses the model selected in the host's shared floating chat, and exports PPTX/PDF/PNG/HTML entirely inside the desktop WebView.",
   "ai_context": {
     "original_prompt": "A built-in Live App for AI-assisted PPT generation, preview, and visual editing.",
     "conversation_id": null,

diff --git a/...ntracts/product-domains/src/miniapp/builtin/assets/ppt-live/src/bitfun-backend-adapter.js b/...ntracts/product-domains/src/miniapp/builtin/assets/ppt-live/src/bitfun-backend-adapter.js
@@ -43,7 +43,6 @@ function installAgentBackend(app) {
         sessionName: 'PPT Live',
         sessionId: options.sessionId,
         appDataWorkspace: options.appDataWorkspace,
-        model: options.model || undefined,
       });
     },
     async call(action, input, options = {}) {
@@ -57,7 +56,6 @@ function installAgentBackend(app) {
         displayText: options.displayText || input.instruction,
         sessionId: options.sessionId,
         appDataWorkspace: options.appDataWorkspace,
-        model: options.model || undefined,
       });
       if (!result?.sessionId || !result?.turnId) {
         throw new Error('PPT Live agent backend did not return sessionId/turnId');