From cf08512e6770ac95391e7d84e4b0f8254a7beb82 Mon Sep 17 00:00:00 2001
From: 0xFirekeeper <0xFirekeeper@gmail.com>
Date: Tue, 22 Sep 2026 20:24:46 +0700
Subject: [PATCH] [SDK] Detect mobile without the viewport width

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
---
 .changeset/ismobile-narrow-viewport.md        |  5 +++
 .../thirdweb/src/utils/web/isMobile.test.ts   | 43 +++++++++++++++++++
 packages/thirdweb/src/utils/web/isMobile.ts   |  7 ---
 3 files changed, 48 insertions(+), 7 deletions(-)
 create mode 100644 .changeset/ismobile-narrow-viewport.md
 create mode 100644 packages/thirdweb/src/utils/web/isMobile.test.ts

diff --git a/.changeset/ismobile-narrow-viewport.md b/.changeset/ismobile-narrow-viewport.md
new file mode 100644
index 00000000000..ca3b76597cf
--- /dev/null
+++ b/.changeset/ismobile-narrow-viewport.md
@@ -0,0 +1,5 @@
+---
+"thirdweb": patch
+---
+
+Show the WalletConnect QR code on desktop browsers with narrow viewports
diff --git a/packages/thirdweb/src/utils/web/isMobile.test.ts b/packages/thirdweb/src/utils/web/isMobile.test.ts
new file mode 100644
index 00000000000..c7f8ecd855a
--- /dev/null
+++ b/packages/thirdweb/src/utils/web/isMobile.test.ts
@@ -0,0 +1,43 @@
+// @vitest-environment happy-dom
+import { afterEach, describe, expect, it, vi } from "vitest";
+import { isMobile } from "./isMobile.js";
+
+const DESKTOP_UA =
+  "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/140.0.0.0 Safari/537.36";
+const IPHONE_UA =
+  "Mozilla/5.0 (iPhone; CPU iPhone OS 18_0 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/18.0 Mobile/15E148 Safari/604.1";
+const ANDROID_UA =
+  "Mozilla/5.0 (Linux; Android 14; Pixel 8) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/140.0.0.0 Mobile Safari/537.36";
+
+function setUserAgent(userAgent: string) {
+  vi.spyOn(navigator, "userAgent", "get").mockReturnValue(userAgent);
+}
+
+function setViewportWidth(width: number) {
+  vi.spyOn(window, "innerWidth", "get").mockReturnValue(width);
+}
+
+describe("isMobile", () => {
+  afterEach(() => {
+    vi.restoreAllMocks();
+  });
+
+  it("returns false for a desktop browser with a narrow viewport", () => {
+    setUserAgent(DESKTOP_UA);
+    setViewportWidth(500);
+
+    expect(isMobile()).toBe(false);
+  });
+
+  it("returns true for iOS", () => {
+    setUserAgent(IPHONE_UA);
+
+    expect(isMobile()).toBe(true);
+  });
+
+  it("returns true for Android", () => {
+    setUserAgent(ANDROID_UA);
+
+    expect(isMobile()).toBe(true);
+  });
+});
diff --git a/packages/thirdweb/src/utils/web/isMobile.ts b/packages/thirdweb/src/utils/web/isMobile.ts
index 4ca8d58dc69..f41e77bae18 100644
--- a/packages/thirdweb/src/utils/web/isMobile.ts
+++ b/packages/thirdweb/src/utils/web/isMobile.ts
@@ -71,12 +71,5 @@ export function isMobile(): boolean {
     return true;
   }
 
-  const isMobileViewport =
-    typeof window !== "undefined" && window.innerWidth < 640;
-
-  if (isMobileViewport) {
-    return true;
-  }
-
   return false;
 }