优化folder打开逻辑

src/components/layout/branch-dropdown.tsx

@@ -345,7 +345,7 @@ export function BranchDropdown({
     setWorktreeOpen(false)
     await runGitTask(t("tasks.newWorktree", { name }), async () => {
       await gitWorktreeAdd(folderPath, name, wtPath)
-      await openFolderWindow(wtPath)
+      await openFolderWindow(wtPath, { newWindow: true })
       await setFolderParentBranch(wtPath, branch)
     })
   }

src/components/layout/folder-name-dropdown.tsx

@@ -54,13 +54,14 @@ export function FolderNameDropdown() {
     if (selected) {
       await openFolderWindow(
         Array.isArray(selected) ? selected[0] : selected,
+        { newWindow: true },
       )
     }
   }
 
   async function handleSelect(path: string) {
     try {
-      await openFolderWindow(path)
+      await openFolderWindow(path, { newWindow: true })
     } catch {
       // ignore
     }

src/components/layout/folder-title-bar.tsx

@@ -82,7 +82,7 @@ export function FolderTitleBar() {
       const result = await openFileDialog({ directory: true, multiple: false })
       if (!result) return
       const selected = Array.isArray(result) ? result[0] : result
-      await openFolderWindow(selected)
+      await openFolderWindow(selected, { newWindow: true })
     } catch (err) {
       console.error("[FolderTitleBar] failed to open folder:", err)
     }

src/contexts/folder-context.tsx

@@ -11,7 +11,8 @@ import {
   type ReactNode,
 } from "react"
 import { toErrorMessage } from "@/lib/app-error"
-import { getFolder, listFolderConversations } from "@/lib/api"
+import { getFolder, listFolderConversations, closeFolderWindow } from "@/lib/api"
+import { isDesktop } from "@/lib/transport"
 import type {
   AgentType,
   AgentStats,
@@ -195,6 +196,22 @@ export function FolderProvider({
     }
   }, [])
 
+  // Web mode: register this tab's name so that window.open(url, "folder-{id}")
+  // from other pages can find and reuse it instead of opening duplicates.
+  // Also notify backend when the folder tab closes.
+  useEffect(() => {
+    if (isDesktop() || !folderId) return
+
+    window.name = `folder-${folderId}`
+
+    const onUnload = () => closeFolderWindow(folderId)
+    window.addEventListener("pagehide", onUnload)
+
+    return () => {
+      window.removeEventListener("pagehide", onUnload)
+    }
+  }, [folderId])
+
   const selectConversation = useCallback((id: number, agentType: AgentType) => {
     setSelectedConversation({ id, agentType })
     setNewConversation(null)

src/lib/api.ts

@@ -839,16 +839,23 @@ export async function gitAddFiles(
 
 // Window management commands
 
-export async function openFolderWindow(path: string): Promise<void> {
+export async function openFolderWindow(
+  path: string,
+  options?: { newWindow?: boolean },
+): Promise<void> {
   if (getTransport().isDesktop()) {
     return getTransport().call("open_folder_window", { path })
   }
-  // Web mode: add folder to DB and navigate to folder page
   const entry = await getTransport().call<{ id: number }>(
     "open_folder_window",
-    { path }
+    { path },
   )
-  window.location.href = `/folder?id=${entry.id}`
+  const url = `/folder?id=${entry.id}`
+  if (options?.newWindow) {
+    window.open(url, `folder-${entry.id}`)
+  } else {
+    window.location.href = url
+  }
 }
 
 export async function openCommitWindow(folderId: number): Promise<void> {
@@ -900,7 +907,25 @@ export async function listOpenFolders(): Promise<FolderHistoryEntry[]> {
 }
 
 export async function focusFolderWindow(folderId: number): Promise<void> {
-  return getTransport().call("focus_folder_window", { folderId })
+  if (getTransport().isDesktop()) {
+    return getTransport().call("focus_folder_window", { folderId })
+  }
+  // Web mode: use named window — reuses existing tab if still open,
+  // otherwise opens a new one.
+  window.open(`/folder?id=${folderId}`, `folder-${folderId}`)
+}
+
+/**
+ * Notify the backend that a folder tab has been closed.
+ * Uses sendBeacon for reliability during page unload.
+ */
+export function closeFolderWindow(folderId: number): void {
+  if (getTransport().isDesktop()) return
+  const token = localStorage.getItem("codeg_token") ?? ""
+  navigator.sendBeacon(
+    `/api/close_folder_window?token=${encodeURIComponent(token)}`,
+    JSON.stringify({ folderId }),
+  )
 }
 
 // Conversation CRUD commands