diff --git a/app/soapbox/normalizers/soapbox/__tests__/soapbox-config.test.ts b/app/soapbox/normalizers/soapbox/__tests__/soapbox-config.test.ts
index 6901254f2..9142a3356 100644
--- a/app/soapbox/normalizers/soapbox/__tests__/soapbox-config.test.ts
+++ b/app/soapbox/normalizers/soapbox/__tests__/soapbox-config.test.ts
@@ -38,6 +38,7 @@ describe('normalizeSoapboxConfig()', () => {
   it('upgrades singleUserModeProfile to redirectRootNoLogin', () => {
     expect(normalizeSoapboxConfig({ singleUserMode: true, singleUserModeProfile: 'alex' }).redirectRootNoLogin).toBe('/@alex');
     expect(normalizeSoapboxConfig({ singleUserMode: true, singleUserModeProfile: '@alex' }).redirectRootNoLogin).toBe('/@alex');
+    expect(normalizeSoapboxConfig({ singleUserMode: true, singleUserModeProfile: 'alex@gleasonator.com' }).redirectRootNoLogin).toBe('/@alex@gleasonator.com');
     expect(normalizeSoapboxConfig({ singleUserMode: false, singleUserModeProfile: 'alex' }).redirectRootNoLogin).toBe('');
   });
 
diff --git a/app/soapbox/normalizers/soapbox/soapbox-config.ts b/app/soapbox/normalizers/soapbox/soapbox-config.ts
index dfac8a777..3b8b2ea91 100644
--- a/app/soapbox/normalizers/soapbox/soapbox-config.ts
+++ b/app/soapbox/normalizers/soapbox/soapbox-config.ts
@@ -6,6 +6,7 @@ import {
 } from 'immutable';
 import trimStart from 'lodash/trimStart';
 
+import { normalizeUsername } from 'soapbox/utils/input';
 import { toTailwind } from 'soapbox/utils/tailwind';
 import { generateAccent } from 'soapbox/utils/theme';
 
@@ -204,7 +205,7 @@ const upgradeSingleUserMode = (soapboxConfig: SoapboxConfigMap): SoapboxConfigMa
 
   if (!redirectRootNoLogin && singleUserMode && singleUserModeProfile) {
     return soapboxConfig
-      .set('redirectRootNoLogin', `/@${singleUserModeProfile.replaceAll('@', '')}`)
+      .set('redirectRootNoLogin', `/@${normalizeUsername(singleUserModeProfile)}`)
       .deleteAll(['singleUserMode', 'singleUserModeProfile']);
   } else {
     return soapboxConfig