fix(chat): refine load all overlay behavior

src/components/chat/hooks/useChatSessionState.ts

@@ -338,12 +338,36 @@ export function useChatSessionState({
         const slot = await sessionStore.fetchMore(selectedSession.id, {
           limit: MESSAGES_PER_PAGE,
         });
-        if (!slot || slot.serverMessages.length === 0) return false;
+        if (!slot) return false;
+        if (slot.serverMessages.length === 0) {
+          if (!slot.hasMore) {
+            setHasMoreMessages(false);
+            allMessagesLoadedRef.current = true;
+            setAllMessagesLoaded(true);
+            if (!loadAllOverlayTimerRef.current) {
+              loadAllOverlayTimerRef.current = setTimeout(() => {
+                setShowLoadAllOverlay(false);
+                loadAllOverlayTimerRef.current = null;
+              }, 2500);
+            }
+          }
+          return false;
+        }
 
         pendingScrollRestoreRef.current = { height: previousScrollHeight, top: previousScrollTop };
         setHasMoreMessages(slot.hasMore);
         setTotalMessages(slot.total);
         setVisibleMessageCount((prev) => prev + MESSAGES_PER_PAGE);
+        if (!slot.hasMore) {
+          allMessagesLoadedRef.current = true;
+          setAllMessagesLoaded(true);
+          if (!loadAllOverlayTimerRef.current) {
+            loadAllOverlayTimerRef.current = setTimeout(() => {
+              setShowLoadAllOverlay(false);
+              loadAllOverlayTimerRef.current = null;
+            }, 2500);
+          }
+        }
         return true;
       } finally {
         isLoadingMoreRef.current = false;
@@ -371,7 +395,7 @@ export function useChatSessionState({
         loadAllOverlayTimerRef.current = setTimeout(() => {
           setShowLoadAllOverlay(false);
           loadAllOverlayTimerRef.current = null;
-        }, 5000);
+        }, 2500);
       }
     } else if (!scrolledNearTop) {
       wasNearTopRef.current = false;
@@ -786,7 +810,7 @@ export function useChatSessionState({
           setLoadAllJustFinished(false);
           setShowLoadAllOverlay(false);
           loadAllFinishedTimerRef.current = null;
-        }, 1000);
+        }, 2500);
       } else {
         allMessagesLoadedRef.current = false;
         setShowLoadAllOverlay(false);

src/components/chat/view/subcomponents/ChatMessagesPane.tsx

@@ -15,6 +15,7 @@ import { groupConsecutiveTools, isToolGroupItem } from '../../utils/toolGrouping
 import MessageComponent from './MessageComponent';
 import ProviderSelectionEmptyState from './ProviderSelectionEmptyState';
 import ToolGroupContainer from './ToolGroupContainer';
+import LoadAllMessagesOverlay from './LoadAllMessagesOverlay';
 
 interface ChatMessagesPaneProps {
   scrollContainerRef: RefObject<HTMLDivElement>;
@@ -219,35 +220,13 @@ function ChatMessagesPane({
             </div>
           )}
 
-          {/* Floating "Load all messages" overlay */}
-          {(showLoadAllOverlay || isLoadingAllMessages || loadAllJustFinished) && (
-            <div className="pointer-events-none sticky top-2 z-20 flex justify-center">
-              {loadAllJustFinished ? (
-                <div className="flex items-center space-x-2 rounded-full bg-green-600 px-4 py-1.5 text-xs font-medium text-white shadow-lg dark:bg-green-500">
-                  <svg className="h-3 w-3" fill="none" stroke="currentColor" viewBox="0 0 24 24">
-                    <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={3} d="M5 13l4 4L19 7" />
-                  </svg>
-                  <span>{t('session.messages.allLoaded')}</span>
-                </div>
-              ) : (
-                <button
-                  className="pointer-events-auto flex items-center space-x-2 rounded-full bg-blue-600 px-4 py-1.5 text-xs font-medium text-white shadow-lg transition-all duration-200 hover:scale-105 hover:bg-blue-700 disabled:cursor-wait disabled:opacity-75 dark:bg-blue-500 dark:hover:bg-blue-600"
-                  onClick={loadAllMessages}
-                  disabled={isLoadingAllMessages}
-                >
-                  {isLoadingAllMessages && (
-                    <div className="h-3 w-3 animate-spin rounded-full border-2 border-white/30 border-t-white" />
-                  )}
-                  <span>
-                    {isLoadingAllMessages
-                      ? t('session.messages.loadingAll')
-                      : <>{t('session.messages.loadAll')} {totalMessages > 0 && `(${totalMessages})`}</>
-                    }
-                  </span>
-                </button>
-              )}
-            </div>
-          )}
+          <LoadAllMessagesOverlay
+            showLoadAllOverlay={showLoadAllOverlay}
+            isLoadingAllMessages={isLoadingAllMessages}
+            loadAllJustFinished={loadAllJustFinished}
+            totalMessages={totalMessages}
+            onLoadAllMessages={loadAllMessages}
+          />
 
           {/* Legacy message count indicator (for non-paginated view) */}
           {!hasMoreMessages && chatMessages.length > visibleMessageCount && (

src/components/chat/view/subcomponents/LoadAllMessagesOverlay.tsx

@@ -0,0 +1,68 @@
+import { useTranslation } from 'react-i18next';
+
+const loadAllOverlayAnimationStyle = `
+@keyframes loadAllOverlayAutoFade {
+  0%, 80% { opacity: 1; }
+  100% { opacity: 0; }
+}
+
+@media (prefers-reduced-motion: reduce) {
+  .load-all-overlay-auto-fade {
+    animation: none !important;
+  }
+}
+`;
+
+interface LoadAllMessagesOverlayProps {
+  showLoadAllOverlay: boolean;
+  isLoadingAllMessages: boolean;
+  loadAllJustFinished: boolean;
+  totalMessages: number;
+  onLoadAllMessages: () => void;
+}
+
+export default function LoadAllMessagesOverlay({
+  showLoadAllOverlay,
+  isLoadingAllMessages,
+  loadAllJustFinished,
+  totalMessages,
+  onLoadAllMessages,
+}: LoadAllMessagesOverlayProps) {
+  const { t } = useTranslation('chat');
+
+  if (!showLoadAllOverlay && !isLoadingAllMessages && !loadAllJustFinished) {
+    return null;
+  }
+
+  return (
+    <div
+      className={`pointer-events-none sticky top-2 z-20 flex justify-center ${!isLoadingAllMessages ? 'load-all-overlay-auto-fade' : ''}`}
+      style={!isLoadingAllMessages ? { animation: 'loadAllOverlayAutoFade 2500ms ease forwards' } : undefined}
+    >
+      <style>{loadAllOverlayAnimationStyle}</style>
+      {loadAllJustFinished ? (
+        <div className="flex items-center space-x-2 rounded-full bg-green-600 px-4 py-1.5 text-xs font-medium text-white shadow-lg dark:bg-green-500">
+          <svg className="h-3 w-3" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+            <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={3} d="M5 13l4 4L19 7" />
+          </svg>
+          <span>{t('session.messages.allLoaded')}</span>
+        </div>
+      ) : (
+        <button
+          className="pointer-events-auto flex items-center space-x-2 rounded-full bg-blue-600 px-4 py-1.5 text-xs font-medium text-white shadow-lg transition-all duration-200 hover:scale-105 hover:bg-blue-700 disabled:cursor-wait disabled:opacity-75 dark:bg-blue-500 dark:hover:bg-blue-600"
+          onClick={onLoadAllMessages}
+          disabled={isLoadingAllMessages}
+        >
+          {isLoadingAllMessages && (
+            <div className="h-3 w-3 animate-spin rounded-full border-2 border-white/30 border-t-white" />
+          )}
+          <span>
+            {isLoadingAllMessages
+              ? t('session.messages.loadingAll')
+              : <>{t('session.messages.loadAll')} {totalMessages > 0 && `(${totalMessages})`}</>}
+          </span>
+        </button>
+      )}
+    </div>
+  );
+}