diff --git a/apps/server/src/provider/model-manifest.json b/apps/server/src/provider/model-manifest.json
index b7531c21c981..d9a1bc0f388e 100644
--- a/apps/server/src/provider/model-manifest.json
+++ b/apps/server/src/provider/model-manifest.json
@@ -1,6 +1,6 @@
 {
   "version": 1,
-  "updatedAt": "2026-09-24T18:40:00Z",
+  "updatedAt": "2026-09-28T19:22:00Z",
   "compatibility": [
     {
       "driver": "codex",
@@ -64,7 +64,7 @@
       "gpt-daybreak-blue-latest",
       "gpt-daybreak-red-latest"
     ],
-    "claudeAgent": ["claude-fable-5-1", "claude-opus-5-5", "claude-sonnet-5"],
+    "claudeAgent": ["claude-fable-5-1", "claude-opus-5-5", "claude-sonnet-5-5"],
     "antigravity": ["gemini-3.8-flash-high", "gemini-3.8-flash-medium", "gemini-3.8-flash-low"]
   },
   "providers": {
@@ -495,6 +495,42 @@
             "claudeCode": {}
           }
         },
+        "sonnet-5-5": {
+          "capabilities": {
+            "optionDescriptors": [
+              {
+                "id": "effort",
+                "label": "Reasoning",
+                "type": "select",
+                "options": [
+                  { "id": "low", "label": "Low" },
+                  { "id": "medium", "label": "Medium", "isDefault": true },
+                  { "id": "high", "label": "High" },
+                  { "id": "xhigh", "label": "Extra High" },
+                  { "id": "max", "label": "Max" },
+                  { "id": "ultrathink", "label": "Ultrathink" }
+                ],
+                "promptInjectedValues": ["ultrathink"]
+              },
+              {
+                "id": "contextWindow",
+                "label": "Context Window",
+                "type": "select",
+                "options": [
+                  { "id": "200k", "label": "200k", "isDefault": true },
+                  { "id": "1m", "label": "1M" }
+                ]
+              }
+            ]
+          },
+          "adapter": {
+            "claudeCode": {
+              "effortMap": { "ultrathink": null },
+              "modelSuffixes": { "contextWindow": { "1m": "[1m]" } },
+              "contextWindowTokens": { "200k": 200000, "1m": 1000000 }
+            }
+          }
+        },
         "sonnet-5": {
           "capabilities": {
             "optionDescriptors": [
@@ -731,11 +767,20 @@
           "status": "legacy",
           "profile": "opus-4-5"
         },
+        {
+          "slug": "claude-sonnet-5-5",
+          "name": "Claude Sonnet 5.5",
+          "aliases": ["sonnet-5.5", "claude-sonnet-5.5"],
+          "status": "current",
+          "badge": "new",
+          "profile": "sonnet-5-5",
+          "adapter": { "claudeCode": { "minVersion": "2.1.284" } }
+        },
         {
           "slug": "claude-sonnet-5",
           "name": "Claude Sonnet 5",
           "aliases": ["sonnet", "sonnet-5", "claude-sonnet-5.0", "claude-sonnet-5-0"],
-          "status": "current",
+          "status": "legacy",
           "profile": "sonnet-5"
         },
         {
diff --git a/apps/web/src/shortcutModifierState.test.ts b/apps/web/src/shortcutModifierState.test.ts
index 4ef4b3b6bf2d..20b63220072d 100644
--- a/apps/web/src/shortcutModifierState.test.ts
+++ b/apps/web/src/shortcutModifierState.test.ts
@@ -1,8 +1,13 @@
-import { describe, expect, it } from "vite-plus/test";
+// @vitest-environment jsdom
+
+import { act, createElement } from "react";
+import { createRoot, type Root } from "react-dom/client";
+import { afterEach, beforeEach, describe, expect, it, vi } from "vite-plus/test";
 
 import {
   areShortcutModifierStatesEqual,
   shortcutModifierStateAfterKeyboardEvent,
+  useShortcutModifierState,
   type ShortcutModifierState,
 } from "./shortcutModifierState";
 
@@ -13,6 +18,67 @@ const emptyState = (): ShortcutModifierState => ({
   shiftKey: false,
 });
 
+describe("useShortcutModifierState", () => {
+  let root: Root;
+  let container: HTMLDivElement;
+
+  beforeEach(() => {
+    vi.stubGlobal("IS_REACT_ACT_ENVIRONMENT", true);
+    container = document.createElement("div");
+    document.body.append(container);
+    root = createRoot(container);
+  });
+
+  afterEach(async () => {
+    await act(async () => root.unmount());
+    container.remove();
+    vi.unstubAllGlobals();
+  });
+
+  it.each(["keyup", "paste", "blur"] as const)(
+    "does not render for unchanged modifiers after %s resets the state",
+    async (reset) => {
+      const render = vi.fn();
+      function Consumer() {
+        render(useShortcutModifierState());
+        return null;
+      }
+      await act(async () => {
+        root.render(createElement(Consumer));
+      });
+      const press = async (type: "keydown" | "keyup", key: string, shiftKey = false) => {
+        await act(async () => {
+          window.dispatchEvent(new KeyboardEvent(type, { key, shiftKey }));
+        });
+      };
+
+      await press("keydown", "Shift", true);
+      expect(render).toHaveBeenLastCalledWith({ ...emptyState(), shiftKey: true });
+      if (reset === "keyup") {
+        await press("keyup", "Shift");
+      } else {
+        await act(async () => {
+          window.dispatchEvent(new Event(reset));
+        });
+      }
+      expect(render).toHaveBeenLastCalledWith(emptyState());
+      render.mockClear();
+
+      for (const key of "typing") {
+        await press("keydown", key);
+        await press("keyup", key);
+      }
+      await act(async () => {
+        window.dispatchEvent(new Event("paste"));
+        window.dispatchEvent(new Event("blur"));
+      });
+      expect(render).not.toHaveBeenCalled();
+      await press("keydown", "Shift", true);
+      expect(render).toHaveBeenCalledExactlyOnceWith({ ...emptyState(), shiftKey: true });
+    },
+  );
+});
+
 function keyboardEventLike(type: "keydown" | "keyup", init: Partial<KeyboardEvent>): KeyboardEvent {
   return {
     type,
diff --git a/apps/web/src/shortcutModifierState.ts b/apps/web/src/shortcutModifierState.ts
index 3abeeaa3e8aa..15d6e0a1bcae 100644
--- a/apps/web/src/shortcutModifierState.ts
+++ b/apps/web/src/shortcutModifierState.ts
@@ -1,4 +1,4 @@
-import { useEffect, useState } from "react";
+import { useEffect, useRef, useState } from "react";
 
 export interface ShortcutModifierState {
   metaKey: boolean;
@@ -28,10 +28,18 @@ export function areShortcutModifierStatesEqual(
 
 export function useShortcutModifierState(): ShortcutModifierState {
   const [state, setState] = useState(EMPTY_SHORTCUT_MODIFIER_STATE);
+  const stateRef = useRef(EMPTY_SHORTCUT_MODIFIER_STATE);
 
   useEffect(() => {
+    const updateState = (next: ShortcutModifierState) => {
+      // Even a no-op state dispatch can cost work in the sidebar's large tree.
+      // Ordinary typing must return before dispatching a React update.
+      if (areShortcutModifierStatesEqual(stateRef.current, next)) return;
+      stateRef.current = next;
+      setState(next);
+    };
     const onKeyboardEvent = (event: KeyboardEvent) => {
-      setState((current) => shortcutModifierStateAfterKeyboardEvent(current, event));
+      updateState(shortcutModifierStateAfterKeyboardEvent(stateRef.current, event));
     };
     // Dictation tools (Wispr Flow) paste with a synthetic ⌘V whose Meta keyup
     // never reaches the page, so the tracked state stays "⌘ held" forever and
@@ -39,11 +47,7 @@ export function useShortcutModifierState(): ShortcutModifierState {
     // treat it like a blur and reset. A physically held modifier re-registers
     // on the next real key event.
     const onResetEvent = () => {
-      setState((current) =>
-        areShortcutModifierStatesEqual(current, EMPTY_SHORTCUT_MODIFIER_STATE)
-          ? current
-          : EMPTY_SHORTCUT_MODIFIER_STATE,
-      );
+      updateState(EMPTY_SHORTCUT_MODIFIER_STATE);
     };
 
     window.addEventListener("keydown", onKeyboardEvent, true);