Using Liferay Custom Tags for Fragments Incorrectly Leads to a Blank Screen Instead of Creating an Error Message

• Type: Regression Bug
• Status: Closed
• Resolution: Duplicate
• Affects Version/s: Master
• Fix Version/s: None
• Component/s: Fragment Administration
• Labels: None
• Fix Priority: 4

Description
When publishing a fragment with incorrect html syntax for Liferay types such as <lfr-editable> or <lfr-widget-xxx>, we have customized error messages to display to the user that their fragment is invalid and why (i.e wrong alias or invalid type for editable). However, instead of doing that, currently a blank screen appears on publish.

Steps to Reproduce

1. Navigate to Site Admin > Build > Page Fragments
2. Create a Fragment with following HTML

   <lfr-widget-wrong-alias></lfr-widget-wrong-alias>
   

3. Click Publish

Expected Result

There is no widget available with alias: wrong-alias

Actual Result
User is navigated to Blank Screen

Reproduced on:
Tomcat 9.0.6 + MySQL 5.7
Portal master GIT ID: edb9113582bde43daefaff1c95c87cabeec94582