diff --git a/packages/ui/src/components/instance/instance-shell2.tsx b/packages/ui/src/components/instance/instance-shell2.tsx
index d8407b1f..8ac7858d 100644
--- a/packages/ui/src/components/instance/instance-shell2.tsx
+++ b/packages/ui/src/components/instance/instance-shell2.tsx
@@ -36,7 +36,6 @@ import { useI18n } from "../../lib/i18n"
 import { getPermissionQueueLength, getQuestionQueueLength } from "../../stores/instances"
 import SessionSidebar from "./shell/SessionSidebar"
 import { useSessionSidebarRequests } from "./shell/useSessionSidebarRequests"
-import RightPanel from "./shell/right-panel/RightPanel"
 import { useDrawerChrome } from "./shell/useDrawerChrome"
 import { getSessionStatus } from "../../stores/session-status"
 import { Maximize2, ShieldAlert } from "lucide-solid"
@@ -64,6 +63,11 @@ const LazyBackgroundProcessOutputDialog = lazy(() =>
   import("../background-process-output-dialog").then((module) => ({ default: module.BackgroundProcessOutputDialog })),
 )
 const LazyPermissionApprovalModal = lazy(() => import("../permission-approval-modal"))
+const LazyRightPanel = lazy(() => import("./shell/right-panel/RightPanel"))
+
+function RightPanelFallback() {
+  return <div class="flex-1 min-h-0" />
+}
 
 interface InstanceShellProps {
   instance: Instance
@@ -499,28 +503,30 @@ const InstanceShell2: Component<InstanceShellProps> = (props) => {
             role="presentation"
             aria-hidden="true"
           />
-          <RightPanel
-            t={t}
-            instanceId={props.instance.id}
-            instance={props.instance}
-            activeSessionId={activeSessionIdForInstance}
-            activeSession={activeSessionForInstance}
-            activeSessionDiffs={activeSessionDiffs}
-            latestTodoState={latestTodoState}
-            backgroundProcessList={backgroundProcessList}
-            onOpenBackgroundOutput={openBackgroundOutput}
-            onStopBackgroundProcess={stopBackgroundProcess}
-            onTerminateBackgroundProcess={terminateBackgroundProcess}
-            isPhoneLayout={isPhoneLayout}
-            rightDrawerWidth={rightDrawerWidth}
-            rightDrawerWidthInitialized={rightDrawerWidthInitialized}
-            rightDrawerState={rightDrawerState}
-            rightPinned={rightPinned}
-            onCloseRightDrawer={closeRightDrawer}
-            onPinRightDrawer={pinRightDrawer}
-            onUnpinRightDrawer={unpinRightDrawer}
-            setContentEl={setRightDrawerContentEl}
-          />
+          <Suspense fallback={<RightPanelFallback />}>
+            <LazyRightPanel
+              t={t}
+              instanceId={props.instance.id}
+              instance={props.instance}
+              activeSessionId={activeSessionIdForInstance}
+              activeSession={activeSessionForInstance}
+              activeSessionDiffs={activeSessionDiffs}
+              latestTodoState={latestTodoState}
+              backgroundProcessList={backgroundProcessList}
+              onOpenBackgroundOutput={openBackgroundOutput}
+              onStopBackgroundProcess={stopBackgroundProcess}
+              onTerminateBackgroundProcess={terminateBackgroundProcess}
+              isPhoneLayout={isPhoneLayout}
+              rightDrawerWidth={rightDrawerWidth}
+              rightDrawerWidthInitialized={rightDrawerWidthInitialized}
+              rightDrawerState={rightDrawerState}
+              rightPinned={rightPinned}
+              onCloseRightDrawer={closeRightDrawer}
+              onPinRightDrawer={pinRightDrawer}
+              onUnpinRightDrawer={unpinRightDrawer}
+              setContentEl={setRightDrawerContentEl}
+            />
+          </Suspense>
         </Box>
       )
     }
@@ -560,28 +566,32 @@ const InstanceShell2: Component<InstanceShellProps> = (props) => {
             aria-hidden="true"
           />
         </Show>
-        <RightPanel
-          t={t}
-          instanceId={props.instance.id}
-          instance={props.instance}
-          activeSessionId={activeSessionIdForInstance}
-          activeSession={activeSessionForInstance}
-          activeSessionDiffs={activeSessionDiffs}
-          latestTodoState={latestTodoState}
-          backgroundProcessList={backgroundProcessList}
-          onOpenBackgroundOutput={openBackgroundOutput}
-          onStopBackgroundProcess={stopBackgroundProcess}
-          onTerminateBackgroundProcess={terminateBackgroundProcess}
-          isPhoneLayout={isPhoneLayout}
-          rightDrawerWidth={rightDrawerWidth}
-          rightDrawerWidthInitialized={rightDrawerWidthInitialized}
-          rightDrawerState={rightDrawerState}
-          rightPinned={rightPinned}
-          onCloseRightDrawer={closeRightDrawer}
-          onPinRightDrawer={pinRightDrawer}
-          onUnpinRightDrawer={unpinRightDrawer}
-          setContentEl={setRightDrawerContentEl}
-        />
+        <Show when={rightOpen() || rightPinned()} fallback={<RightPanelFallback />}>
+          <Suspense fallback={<RightPanelFallback />}>
+            <LazyRightPanel
+              t={t}
+              instanceId={props.instance.id}
+              instance={props.instance}
+              activeSessionId={activeSessionIdForInstance}
+              activeSession={activeSessionForInstance}
+              activeSessionDiffs={activeSessionDiffs}
+              latestTodoState={latestTodoState}
+              backgroundProcessList={backgroundProcessList}
+              onOpenBackgroundOutput={openBackgroundOutput}
+              onStopBackgroundProcess={stopBackgroundProcess}
+              onTerminateBackgroundProcess={terminateBackgroundProcess}
+              isPhoneLayout={isPhoneLayout}
+              rightDrawerWidth={rightDrawerWidth}
+              rightDrawerWidthInitialized={rightDrawerWidthInitialized}
+              rightDrawerState={rightDrawerState}
+              rightPinned={rightPinned}
+              onCloseRightDrawer={closeRightDrawer}
+              onPinRightDrawer={pinRightDrawer}
+              onUnpinRightDrawer={unpinRightDrawer}
+              setContentEl={setRightDrawerContentEl}
+            />
+          </Suspense>
+        </Show>
       </Drawer>
 
     )
diff --git a/packages/ui/src/components/instance/shell/useSessionCache.ts b/packages/ui/src/components/instance/shell/useSessionCache.ts
index 0e3a3476..8839d569 100644
--- a/packages/ui/src/components/instance/shell/useSessionCache.ts
+++ b/packages/ui/src/components/instance/shell/useSessionCache.ts
@@ -2,10 +2,30 @@ import { createEffect, createSignal, type Accessor } from "solid-js"
 import { messageStoreBus } from "../../../stores/message-v2/bus"
 import { clearSessionRenderCache } from "../../message-block"
 import { getLogger } from "../../../lib/logger"
+import { runtimeEnv } from "../../../lib/runtime-env"
 
 const log = getLogger("session")
 
-const SESSION_CACHE_LIMIT = 5
+function getSessionCacheLimit() {
+  if (runtimeEnv.platform === "mobile") {
+    return 2
+  }
+
+  if (runtimeEnv.host === "tauri") {
+    return 3
+  }
+
+  if (typeof navigator !== "undefined") {
+    const deviceMemory = (navigator as Navigator & { deviceMemory?: number }).deviceMemory
+    if (typeof deviceMemory === "number" && deviceMemory <= 4) {
+      return 3
+    }
+  }
+
+  return 5
+}
+
+const SESSION_CACHE_LIMIT = getSessionCacheLimit()
 
 type SessionCacheOptions = {
   instanceId: Accessor<string>
diff --git a/packages/ui/src/components/session/session-view.tsx b/packages/ui/src/components/session/session-view.tsx
index ba78382c..b234b09b 100644
--- a/packages/ui/src/components/session/session-view.tsx
+++ b/packages/ui/src/components/session/session-view.tsx
@@ -131,9 +131,15 @@ export const SessionView: Component<SessionViewProps> = (props) => {
 
   createEffect(() => {
     const currentSession = session()
-    if (currentSession) {
-      loadMessages(props.instanceId, currentSession.id).catch((error) => log.error("Failed to load messages", error))
+    if (!currentSession) {
+      return
     }
+
+    if (props.isActive === false) {
+      return
+    }
+
+    loadMessages(props.instanceId, currentSession.id).catch((error) => log.error("Failed to load messages", error))
   })
 
   function registerPromptInputApi(api: PromptInputApi) {
diff --git a/packages/ui/src/lib/ui-bootstrap-cache.ts b/packages/ui/src/lib/ui-bootstrap-cache.ts
new file mode 100644
index 00000000..422d3887
--- /dev/null
+++ b/packages/ui/src/lib/ui-bootstrap-cache.ts
@@ -0,0 +1,48 @@
+export type UiBootstrapTheme = "light" | "dark" | "system"
+
+export interface UiBootstrapCacheSnapshot {
+  theme?: UiBootstrapTheme
+  locale?: string
+}
+
+const UI_BOOTSTRAP_CACHE_KEY = "codenomad:ui-bootstrap"
+
+export function readUiBootstrapCache(): UiBootstrapCacheSnapshot {
+  if (typeof window === "undefined" || typeof window.localStorage === "undefined") {
+    return {}
+  }
+
+  try {
+    const raw = window.localStorage.getItem(UI_BOOTSTRAP_CACHE_KEY)
+    if (!raw) {
+      return {}
+    }
+
+    const parsed = JSON.parse(raw) as UiBootstrapCacheSnapshot
+    if (!parsed || typeof parsed !== "object") {
+      return {}
+    }
+
+    return {
+      theme:
+        parsed.theme === "light" || parsed.theme === "dark" || parsed.theme === "system"
+          ? parsed.theme
+          : undefined,
+      locale: typeof parsed.locale === "string" ? parsed.locale : undefined,
+    }
+  } catch {
+    return {}
+  }
+}
+
+export function writeUiBootstrapCache(snapshot: UiBootstrapCacheSnapshot) {
+  if (typeof window === "undefined" || typeof window.localStorage === "undefined") {
+    return
+  }
+
+  try {
+    window.localStorage.setItem(UI_BOOTSTRAP_CACHE_KEY, JSON.stringify(snapshot))
+  } catch {
+    /* noop */
+  }
+}
diff --git a/packages/ui/src/main.tsx b/packages/ui/src/main.tsx
index cc6c6f1e..6ddc40e1 100644
--- a/packages/ui/src/main.tsx
+++ b/packages/ui/src/main.tsx
@@ -5,7 +5,7 @@ import { ConfigProvider } from "./stores/preferences"
 import { InstanceConfigProvider } from "./stores/instance-config"
 import { runtimeEnv } from "./lib/runtime-env"
 import { I18nProvider, preloadLocaleMessages } from "./lib/i18n"
-import { storage } from "./lib/storage"
+import { readUiBootstrapCache } from "./lib/ui-bootstrap-cache"
 import "./index.css"
 import "@git-diff-view/solid/styles/diff-view-pure.css"
 
@@ -29,22 +29,16 @@ async function bootstrap() {
     // (and then refine once persisted config loads).
     document.documentElement.removeAttribute("data-theme")
 
-    try {
-      const uiConfig = await storage.loadConfigOwner("ui")
-      const theme = (uiConfig as any)?.theme ?? "system"
-      const locale = (uiConfig as any)?.settings?.locale
+    const bootstrapCache = readUiBootstrapCache()
+    const theme = bootstrapCache.theme ?? "system"
 
-      if (theme === "system") {
-        document.documentElement.removeAttribute("data-theme")
-      } else {
-        document.documentElement.setAttribute("data-theme", theme)
-      }
-
-      await preloadLocaleMessages(typeof locale === "string" ? locale : undefined)
-    } catch {
-      // If config fails to load, fall back to CSS defaults.
-      await preloadLocaleMessages(undefined)
+    if (theme === "system") {
+      document.documentElement.removeAttribute("data-theme")
+    } else {
+      document.documentElement.setAttribute("data-theme", theme)
     }
+
+    await preloadLocaleMessages(bootstrapCache.locale)
   }
 
   render(
diff --git a/packages/ui/src/stores/preferences.tsx b/packages/ui/src/stores/preferences.tsx
index 8ac2ead0..442adfca 100644
--- a/packages/ui/src/stores/preferences.tsx
+++ b/packages/ui/src/stores/preferences.tsx
@@ -1,6 +1,7 @@
-import { createContext, createMemo, createSignal, onMount, useContext } from "solid-js"
+import { createContext, createEffect, createMemo, createSignal, onMount, useContext } from "solid-js"
 import type { Accessor, ParentComponent } from "solid-js"
 import { storage, type OwnerBucket } from "../lib/storage"
+import { writeUiBootstrapCache } from "../lib/ui-bootstrap-cache"
 import {
   ensureInstanceConfigLoaded,
   getInstanceConfig,
@@ -598,6 +599,14 @@ const configContextValue: ConfigContextValue = {
 }
 
 export const ConfigProvider: ParentComponent = (props) => {
+  createEffect(() => {
+    const bucket = uiConfigBucket()
+    writeUiBootstrapCache({
+      theme: bucket.theme,
+      locale: bucket.settings?.locale,
+    })
+  })
+
   onMount(() => {
     ensureLoaded().catch((error: unknown) => {
       log.error("Failed to initialize settings", error)