diff --git a/packages/web/server/lib/package-manager.js b/packages/web/server/lib/package-manager.js
index 7e8f9195..4fb390f6 100644
--- a/packages/web/server/lib/package-manager.js
+++ b/packages/web/server/lib/package-manager.js
@@ -655,16 +655,35 @@ export async function getLatestVersion() {
 /**
  * Compare semver-like version strings.
  */
+function parseVersionForComparison(value) {
+  const normalized = String(value || '').replace(/^v/, '').split('+')[0];
+  const prereleaseIndex = normalized.indexOf('-');
+  const core = prereleaseIndex >= 0 ? normalized.slice(0, prereleaseIndex) : normalized;
+  const parts = core.split('.').map((part) => {
+    const parsed = Number.parseInt(part || '0', 10);
+    return Number.isFinite(parsed) ? parsed : 0;
+  });
+
+  return {
+    parts,
+    prerelease: prereleaseIndex >= 0,
+  };
+}
+
 function compareVersions(left, right) {
-  const a = String(left || '').replace(/^v/, '').split('.').map((part) => Number.parseInt(part || '0', 10));
-  const b = String(right || '').replace(/^v/, '').split('.').map((part) => Number.parseInt(part || '0', 10));
-  const length = Math.max(a.length, b.length);
+  const a = parseVersionForComparison(left);
+  const b = parseVersionForComparison(right);
+  const length = Math.max(a.parts.length, b.parts.length);
 
   for (let index = 0; index < length; index += 1) {
-    const diff = (a[index] || 0) - (b[index] || 0);
+    const diff = (a.parts[index] || 0) - (b.parts[index] || 0);
     if (diff !== 0) return diff;
   }
 
+  if (a.prerelease !== b.prerelease) {
+    return a.prerelease ? -1 : 1;
+  }
+
   return 0;
 }
 
diff --git a/packages/web/server/lib/package-manager.test.js b/packages/web/server/lib/package-manager.test.js
index e8419e42..3eef72e9 100644
--- a/packages/web/server/lib/package-manager.test.js
+++ b/packages/web/server/lib/package-manager.test.js
@@ -34,14 +34,16 @@ function createFetchMock() {
 
 describe('checkForUpdates', () => {
   let fetchMock;
+  let originalFetch;
 
   beforeEach(() => {
     fetchMock = createFetchMock();
-    vi.stubGlobal('fetch', fetchMock);
+    originalFetch = globalThis.fetch;
+    globalThis.fetch = fetchMock;
   });
 
   afterEach(() => {
-    vi.unstubAllGlobals();
+    globalThis.fetch = originalFetch;
   });
 
   // --- Scenario: API says update available, npm confirms ---
@@ -98,6 +100,21 @@ describe('checkForUpdates', () => {
     expect(result.available).toBe(false);
   });
 
+  it('returns available=false when npm only has a prerelease of the current version', async () => {
+    fetchMock
+      .when('api.openchamber.dev', Promise.reject(new Error('Network error')))
+      .when('registry.npmjs.org', {
+        ok: true,
+        json: async () => ({
+          'dist-tags': { latest: '1.10.0-beta.1' },
+        }),
+      });
+
+    const result = await checkForUpdates({ currentVersion: '1.10.0' });
+
+    expect(result.available).toBe(false);
+  });
+
   it('does not cross-check desktop update claims against npm', async () => {
     fetchMock
       .when('api.openchamber.dev', {