Email Sender Verification Disappears upon Empty Input

• Type: Regression Bug
• Status: Verified
• Resolution: Unresolved
• Affects Version/s: 7.1.X
• Fix Version/s: 7.1.10 DXP FP21
• Component/s: Portal Configuration > Portal Settings
• Labels:
  • liferay-fixpack-dxp-21-7110
• Fix Priority: 2
• Git Pull Request: https://github.com/liferay/liferay-portal-ee/pull/21517

After the introduction of LPS-103703 in 7.1.x , the following behavior is expected to work:

1. Start Liferay in 7.1.x.
2. Navigate to Control Panel > Configuration > Instance Settings
3. Scroll down until you see "Email Notifications->Sender"
4. Set "Address" field to blank > Save

Expected Behavior:
The page stays on Configuration->Email Notifications->Sender section and throws a UI error saying the field must have a valid email address and/or field is required.

Actual Behavior:
The page swaps to Identification tab and throws an EmailAddressException there. When you swap back to Email Notifications tab, you can see that the Sender tab is not loaded, and only after clicking the Sender tab again, it loads with the error.

Tested in:
7.1.x: 158e39717de54fe2243c6c45f5d8e3257d2ac9f1