diff --git a/lib/shared/sidebar-item-utils.js b/lib/shared/sidebar-item-utils.js
--- a/lib/shared/sidebar-item-utils.js
+++ b/lib/shared/sidebar-item-utils.js
@@ -132,7 +132,7 @@
 ): Promise<$ReadOnlyArray<SidebarThreadItem>> {
   if (sidebarInfos.length === 0) {
     return [];
-  } else if (sidebarInfos.length <= maxUnreadSidebars) {
+  } else if (sidebarInfos.length <= maxUnreadSidebars + 1) {
     return await getAllFinalSidebarItems(sidebarInfos);
   }
 
@@ -164,20 +164,22 @@
     loaders.filter(loader => loader.threadInfo.currentUser.unread),
   );
 
-  const topGeneralPromise =
-    generalCache.loadMostRecentChatThreadItems(maxReadSidebars);
-  const topUnreadPromise =
-    unreadCache.loadMostRecentChatThreadItems(maxUnreadSidebars);
+  const topGeneralPromise = generalCache.loadMostRecentChatThreadItems(
+    maxReadSidebars + 1,
+  );
+  const topUnreadPromise = unreadCache.loadMostRecentChatThreadItems(
+    maxUnreadSidebars + 1,
+  );
   const [topGeneralResults, topUnreadResults] = await Promise.all([
     topGeneralPromise,
     topUnreadPromise,
   ]);
 
-  const topResults = topUnreadResults.slice(0, maxUnreadSidebars);
+  const topResults = topUnreadResults.slice(0, maxUnreadSidebars + 1);
   const topThreadIDs = new Set([
     ...topResults.map(result => result.threadInfo.id),
   ]);
-  const generalResults = topGeneralResults.slice(0, maxReadSidebars);
+  const generalResults = topGeneralResults.slice(0, maxReadSidebars + 1);
   for (const result of generalResults) {
     if (!topThreadIDs.has(result.threadInfo.id)) {
       topResults.push(result);