diff --git a/src/core/server/ui_settings/ui_settings_client.test.ts b/src/core/server/ui_settings/ui_settings_client.test.ts
index 72461653d652..a7aa95ebab91 100644
--- a/src/core/server/ui_settings/ui_settings_client.test.ts
+++ b/src/core/server/ui_settings/ui_settings_client.test.ts
@@ -624,6 +624,29 @@ describe('ui settings', () => {
       expect(await uiSettings.get('dateFormat')).toBe('foo');
     });
 
+    it('returns the overridden value for key theme:version', async () => {
+      const opensearchDocSource = { 'theme:version': 'v8 (beta)' };
+      const overrides = { 'theme:version': 'v7' };
+      const { uiSettings } = setup({ opensearchDocSource, overrides });
+
+      expect(await uiSettings.get('theme:version')).toBe('v7');
+    });
+
+    it('returns the overridden value for key theme:version when doc source is empty', async () => {
+      const opensearchDocSource = {};
+      const overrides = { 'theme:version': 'v7' };
+      const { uiSettings } = setup({ opensearchDocSource, overrides });
+
+      expect(await uiSettings.get('theme:version')).toBe('v7');
+    });
+
+    it('rewrites the key theme:version value without override', async () => {
+      const opensearchDocSource = { 'theme:version': 'v8 (beta)' };
+      const { uiSettings } = setup({ opensearchDocSource });
+
+      expect(await uiSettings.get('theme:version')).toBe('v8 (beta)');
+    });
+
     it('returns the default value for an override with value null', async () => {
       const opensearchDocSource = { dateFormat: 'YYYY-MM-DD' };
       const overrides = { dateFormat: null };
diff --git a/src/core/server/ui_settings/ui_settings_config.ts b/src/core/server/ui_settings/ui_settings_config.ts
index 4c3dd0e4dcf5..634fb5c62d55 100644
--- a/src/core/server/ui_settings/ui_settings_config.ts
+++ b/src/core/server/ui_settings/ui_settings_config.ts
@@ -38,7 +38,12 @@ const deprecations: ConfigDeprecationProvider = ({ unused, renameFromRoot }) =>
 ];
 
 const configSchema = schema.object({
-  overrides: schema.object({}, { unknowns: 'allow' }),
+  overrides: schema.object(
+    {
+      'theme:version': schema.string({ defaultValue: 'v7' }),
+    },
+    { unknowns: 'allow' }
+  ),
 });
 
 export type UiSettingsConfigType = TypeOf<typeof configSchema>;