diff --git a/.changeset/fix-quick-add-model-filter.md b/.changeset/fix-quick-add-model-filter.md
new file mode 100644
index 0000000000..b47f22fcc5
--- /dev/null
+++ b/.changeset/fix-quick-add-model-filter.md
@@ -0,0 +1,7 @@
+---
+"@runfusion/fusion": patch
+---
+
+summary: Fix the Quick Add model dropdown filter box so typing narrows the model list.
+category: fix
+dev: The quick-entry model menu's blanket onMouseDown preventDefault crossed the React portal boundary and suppressed focus on CustomModelDropdown's search input.
diff --git a/packages/dashboard/app/components/QuickEntryBox.tsx b/packages/dashboard/app/components/QuickEntryBox.tsx
index 414b3bb544..12b05ee9fe 100644
--- a/packages/dashboard/app/components/QuickEntryBox.tsx
+++ b/packages/dashboard/app/components/QuickEntryBox.tsx
@@ -2402,7 +2402,19 @@ export function QuickEntryBox({ onCreate, onMoveTask, addToast, tasks = [], avai
             <div
               ref={modelMenuPortalRef}
               className="model-nested-menu model-nested-menu--portal"
-              onMouseDown={(e) => e.preventDefault()}
+              onMouseDown={(e) => {
+                /*
+                FNXC:QuickAddModels 2026-08-12-21:51:
+                React synthetic mouse events cross createPortal boundaries, so this composer-focus guard
+                must exempt form controls and the portaled model dropdown or preventDefault suppresses
+                focus for its filter input. Plain menu chrome still preserves the quick-entry focus.
+                */
+                const target = e.target as Element;
+                if (target.closest("input, textarea, select, [contenteditable], .model-combobox-dropdown--portal")) {
+                  return;
+                }
+                e.preventDefault();
+              }}
               data-testid="model-nested-menu"
               style={{
                 position: "fixed",
diff --git a/packages/dashboard/app/components/__tests__/QuickEntryBox-model-filter.test.tsx b/packages/dashboard/app/components/__tests__/QuickEntryBox-model-filter.test.tsx
new file mode 100644
index 0000000000..8e759ca64a
--- /dev/null
+++ b/packages/dashboard/app/components/__tests__/QuickEntryBox-model-filter.test.tsx
@@ -0,0 +1,113 @@
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+import { render, screen } from "@testing-library/react";
+import userEvent from "@testing-library/user-event";
+import { QuickEntryBox } from "../QuickEntryBox";
+import type { ModelInfo } from "../../api";
+
+vi.mock("../../api", () => ({
+  fetchModels: vi.fn(),
+  fetchSettings: vi.fn().mockResolvedValue({
+    modelPresets: [],
+    autoSelectModelPreset: false,
+    defaultPresetBySize: {},
+    maxConcurrent: 2,
+    maxWorktrees: 4,
+    pollIntervalMs: 30_000,
+    groupOverlappingFiles: true,
+    autoMerge: true,
+  }),
+  fetchAgents: vi.fn().mockResolvedValue([]),
+  checkDuplicateTasks: vi.fn().mockResolvedValue([]),
+  uploadAttachment: vi.fn().mockResolvedValue({}),
+  fetchWorkflowOptionalSteps: vi.fn().mockResolvedValue([]),
+  updateGlobalSettings: vi.fn().mockResolvedValue({}),
+}));
+
+vi.mock("../../hooks/useNodes", () => ({
+  useNodes: () => ({
+    nodes: [],
+    loading: false,
+    error: null,
+    refresh: vi.fn(),
+    register: vi.fn(),
+    update: vi.fn(),
+    unregister: vi.fn(),
+    healthCheck: vi.fn(),
+  }),
+}));
+
+vi.mock("../../hooks/useComposerDictation", () => ({
+  useComposerDictation: () => ({ micProps: { enabled: false, supported: false, state: "idle", start: vi.fn(), stop: vi.fn() } }),
+}));
+
+const models: ModelInfo[] = [
+  { provider: "anthropic", id: "claude-sonnet", name: "Claude Sonnet", reasoning: true, contextWindow: 200_000 },
+  { provider: "openai", id: "gpt-4o", name: "GPT-4o", reasoning: false, contextWindow: 128_000 },
+];
+
+const originalInnerWidth = Object.getOwnPropertyDescriptor(window, "innerWidth");
+
+function setViewport(width: number) {
+  Object.defineProperty(window, "innerWidth", { configurable: true, value: width });
+}
+
+function renderQuickEntry() {
+  return render(
+    <QuickEntryBox
+      addToast={vi.fn()}
+      availableModels={models}
+      onCreate={vi.fn().mockResolvedValue(undefined)}
+      projectId="quick-entry-model-filter"
+    />,
+  );
+}
+
+/**
+ * FNXC:QuickAddModels 2026-08-12-21:51:
+ * This regression uses the real portaled CustomModelDropdown because a stub cannot prove that
+ * a React portal ancestor's mousedown handling preserves focus for the nested filter input.
+ */
+describe("QuickEntryBox model filter", () => {
+  beforeEach(() => {
+    localStorage.clear();
+    document.body.innerHTML = "";
+  });
+
+  afterEach(() => {
+    if (originalInnerWidth) {
+      Object.defineProperty(window, "innerWidth", originalInnerWidth);
+    }
+    localStorage.clear();
+  });
+
+  it.each([
+    { lane: "executor", width: 1280, query: "clau", expected: "Claude Sonnet", absent: "GPT-4o" },
+    { lane: "validator", width: 375, query: "no-match", expected: null, absent: "Claude Sonnet" },
+  ])("focuses and filters the $lane model dropdown at $widthpx", async ({ lane, width, query, expected, absent }) => {
+    setViewport(width);
+    const user = userEvent.setup();
+    renderQuickEntry();
+
+    const textarea = screen.getByTestId("quick-entry-input") as HTMLTextAreaElement;
+    await user.type(textarea, "Keep this description");
+    await user.click(screen.getByTestId("quick-entry-models"));
+    await user.click(screen.getByTestId(`model-menu-${lane}`));
+    await user.click(screen.getByRole("button", { name: `${lane} model` }));
+
+    const filterInput = await screen.findByPlaceholderText("Filter models…");
+    await user.click(filterInput);
+    expect(document.activeElement).toBe(filterInput);
+    await user.keyboard(query);
+
+    expect(filterInput).toHaveValue(query);
+    expect(screen.getByTestId("model-nested-menu")).toBeInTheDocument();
+    expect(textarea).toHaveValue("Keep this description");
+
+    if (expected) {
+      expect(screen.getByText(expected)).toBeInTheDocument();
+    } else {
+      expect(screen.getByText(/No models match/)).toBeInTheDocument();
+    }
+    expect(screen.queryByText(absent)).not.toBeInTheDocument();
+  });
+});