diff --git a/packages/toolkit/core-kit/src/regex.test.ts b/packages/toolkit/core-kit/src/regex.test.ts
new file mode 100644
index 000000000..e56fa572f
--- /dev/null
+++ b/packages/toolkit/core-kit/src/regex.test.ts
@@ -0,0 +1,18 @@
+import { domainRegEx } from './regex.js';
+
+describe('Regular expressions should work as expected', () => {
+  it('should allow valid domains that consists of 3 parts. E.g. foo.bar.com', () => {
+    expect(domainRegEx.test('foo.bar.com')).toBe(true);
+    expect(domainRegEx.test('foo1.bar.com')).toBe(true);
+    expect(domainRegEx.test('foo.bar1.com')).toBe(true);
+    expect(domainRegEx.test('1foo.bar.com')).toBe(true);
+    expect(domainRegEx.test('f.bar.co')).toBe(true);
+    expect(domainRegEx.test('f.b.com')).toBe(true);
+    expect(domainRegEx.test('1.b.tk')).toBe(true);
+  });
+
+  it('should not allow domains that consists of 2 parts. E.g. bar.com', () => {
+    expect(domainRegEx.test('bar.com')).toBe(false);
+    expect(domainRegEx.test('b.co')).toBe(false);
+  });
+});
diff --git a/packages/toolkit/core-kit/src/regex.ts b/packages/toolkit/core-kit/src/regex.ts
index 74cbcc5e6..688a77dfb 100644
--- a/packages/toolkit/core-kit/src/regex.ts
+++ b/packages/toolkit/core-kit/src/regex.ts
@@ -8,5 +8,4 @@ export const hexColorRegEx = /^#[\da-f]{3}([\da-f]{3})?$/i;
 export const dateRegex = /^\d{4}(-\d{2}){2}/;
 export const noSpaceRegEx = /^\S+$/;
 /** Full domain that consists of at least 3 parts, e.g. foo.bar.com */
-export const domainRegEx =
-  /^[\dA-Za-z][\dA-Za-z-]*[\dA-Za-z](\.[\dA-Za-z][\dA-Za-z-]*[\dA-Za-z]){2,}$/;
+export const domainRegEx = /^[\dA-Za-z]+(\.[\dA-Za-z]+){2,}$/;