diff --git a/web/src/core-bridge/worker/account.ts b/web/src/core-bridge/worker/account.ts
index 227aa28..a8a97bb 100644
--- a/web/src/core-bridge/worker/account.ts
+++ b/web/src/core-bridge/worker/account.ts
@@ -260,7 +260,8 @@ export async function acceptInvitation(channelId: string): Promise<void> {
   const invitation = (await listAccountInvitations()).find((row) => row.channel_id === channelId);
   if (!invitation) throw new Error('邀请已失效');
   const link = await openChannelGrant(invitation.payload, session.username, channelId, session.profile.keys.privateKey, 'member', self.location.origin);
-  stillActive(session); await joinChannel({ link }); await syncVault();
+  // 保险库同步(约 5 次往返)放到后台,不让用户等着:频道资源已在本机保存,可以直接打开
+  stillActive(session); await joinChannel({ link }); scheduleSync();
 }
 export async function inviteChannelUser(channelId: string, input: string): Promise<void> {
   requireAccount(); const username = usernameOf(input); const { session, resource } = await getSession(channelId);
diff --git a/web/src/core-bridge/worker/channelDataKeys.ts b/web/src/core-bridge/worker/channelDataKeys.ts
index 11d65cb..9221ebc 100644
--- a/web/src/core-bridge/worker/channelDataKeys.ts
+++ b/web/src/core-bridge/worker/channelDataKeys.ts
@@ -27,7 +27,15 @@ export function attachDataKeys(session: ChannelSession, resource: SavedResource)
     objectKeys.set(`${resource.id}:${itemId}`, unwrapped); return unwrapped;
   };
 }
-export async function readDataKeys(resource: SavedResource, session: ChannelSession): Promise<{ state: CryptoState; keys: Record<string, string> }> {
+type DataKeys = { state: CryptoState; keys: Record<string, string> };
+const pendingKeys = new Map<string, Promise<DataKeys>>();
+/** 同一空间同时发起的读取合并成一次请求 */
+export function readDataKeys(resource: SavedResource, session: ChannelSession): Promise<DataKeys> {
+  let task = pendingKeys.get(resource.id);
+  if (!task) { task = loadDataKeys(resource, session).finally(() => pendingKeys.delete(resource.id)); pendingKeys.set(resource.id, task); }
+  return task;
+}
+async function loadDataKeys(resource: SavedResource, session: ChannelSession): Promise<DataKeys> {
   const state = await apiFetch(`/spaces/${resource.id}/crypto`, { headers: session.authHeaders(session.can('owner') ? 'owner' : 'read') }).then(r => r.json() as Promise<CryptoState>);
   states.set(resource.id, state);
   const latest = await getResource(resource.id); const keys = { ...latest?.domainKeys };
diff --git a/web/src/core-bridge/worker/channelEvents.ts b/web/src/core-bridge/worker/channelEvents.ts
index 5505a60..3062aa2 100644
--- a/web/src/core-bridge/worker/channelEvents.ts
+++ b/web/src/core-bridge/worker/channelEvents.ts
@@ -129,15 +129,19 @@ export async function channelMetadata(resource: SavedResource, session: ChannelS
 }
 
 export async function syncChannel(resource: SavedResource, session: ChannelSession, signal: AbortSignal): Promise<number> {
-  if (resource.mode === 'enc') await readDataKeys(resource, session);
+  // reset 必须同步发出:connectChannel 随后并行拉取频道信息,它们的结果要落在 reset 之后
   publishWorkspace(resource.id, { t: 'reset' });
   clearFileCatalog(resource.id);
   readers.set(resource.id, session.createItemReader());
+  // 密钥与第一页日志互不依赖,同时发出,首次打开少等一个往返
+  const keys = resource.mode === 'enc' ? readDataKeys(resource, session) : undefined;
+  keys?.catch(() => undefined);
   let from = 0;
-  for (;;) {
+  for (let first = true; ; first = false) {
     const response = await apiFetch(`/channels/${resource.id}/log?from=${from}&limit=200`, {
       headers: session.authHeaders('read'), signal,
     });
+    if (first) await keys;
     const records = parseLogRecords(new Uint8Array(await response.arrayBuffer()));
     for (const record of records) {
       await applyChannelRecord(resource, session, record);
diff --git a/web/src/core-bridge/worker/channelResources.ts b/web/src/core-bridge/worker/channelResources.ts
index eb3b11a..7264d69 100644
--- a/web/src/core-bridge/worker/channelResources.ts
+++ b/web/src/core-bridge/worker/channelResources.ts
@@ -8,7 +8,7 @@ import { channelCache, isOfflineFailure } from './resourceMetadata';
 import { accountToken } from './accountSession';
 import { attachDataKeys, initializeChannelKeys } from './channelDataKeys';
 import type { ChannelSettingsPatch as SettingsRequest, JoinResult, MemberBody } from '../generated/api';
-import { getSession, sessions } from './sessions';
+import { freshlyJoined, getSession, sessions } from './sessions';
 import { makeLink } from './links';
 import { toChannelInfo, type ChannelWire } from './wire';
 import { stopChannel } from './channelTransport';
@@ -90,6 +90,7 @@ export async function joinChannel(input: { link: ParsedChannelLink; password?: s
     };
     await saveResource(resource);
     sessions.set(id, session);
+    freshlyJoined.set(id, Date.now());
     return toChannelInfo(info, resource);
   } catch (error) {
     session.dispose();
diff --git a/web/src/core-bridge/worker/channelTransport.ts b/web/src/core-bridge/worker/channelTransport.ts
index 1d1c2bb..04416f5 100644
--- a/web/src/core-bridge/worker/channelTransport.ts
+++ b/web/src/core-bridge/worker/channelTransport.ts
@@ -1,5 +1,5 @@
 import { IntegrityError } from '@webdrop/core';
-import { active, getSession } from './sessions';
+import { active, freshlyJoined, getSession } from './sessions';
 import { apiFetch, type ApiError } from './http';
 import { publishWorkspace } from './presentation';
 import { channelMetadata, processChannelBytes, syncChannel } from './channelEvents';
@@ -20,7 +20,9 @@ export async function connectChannel(id: string): Promise<void> {
     if (signal.aborted) return;
     if (resource.kind !== 'channel') throw new Error('资源类型不匹配');
     // Device sessions can be revoked independently of account membership; rejoin idempotently.
-    await apiFetch(`/channels/${id}/join`, { method: 'POST', headers: session.authHeaders(session.can('owner') ? 'owner' : 'read'), signal });
+    const joinedAt = freshlyJoined.get(id); freshlyJoined.delete(id);
+    if (joinedAt === undefined || Date.now() - joinedAt > 60_000)
+      await apiFetch(`/channels/${id}/join`, { method: 'POST', headers: session.authHeaders(session.can('owner') ? 'owner' : 'read'), signal });
     if (resource.needsJoin) {
       if (session.can('owner')) await channelMetadata(resource, session);
       resource.needsJoin = false;
@@ -47,9 +49,8 @@ export async function connectChannel(id: string): Promise<void> {
     while (!signal.aborted) {
       try {
         if (!initialized) {
-          stream.cursor = await syncChannel(resource, session, signal);
+          [stream.cursor] = await Promise.all([syncChannel(resource, session, signal), channelMetadata(resource, session)]);
           if (signal.aborted) break;
-          await channelMetadata(resource, session);
           await flushOutbox(resource, session);
           initialized = true;
           publishWorkspace(id, { t: 'ready' });
diff --git a/web/src/core-bridge/worker/sessions.ts b/web/src/core-bridge/worker/sessions.ts
index f9baeb6..d99c5d0 100644
--- a/web/src/core-bridge/worker/sessions.ts
+++ b/web/src/core-bridge/worker/sessions.ts
@@ -8,6 +8,8 @@ import { clearWorkspaceStructures } from './workspaceStructure';
 import { attachDataKeys, clearDataKeys } from './channelDataKeys';
 export const sessions = new Map<string, ChannelSession>();
 export const readers = new Map<string, ReturnType<ChannelSession['createItemReader']>>();
+/** 刚加入的频道 → 加入时间;connectChannel 据此跳过紧接着的重复 join(省一次往返) */
+export const freshlyJoined = new Map<string, number>();
 export const active = new Map<string, AbortController>();
 export const blobs = new Map<string, Blob>();
 const opening = new Map<string, Promise<ChannelSession>>();