RSS Configuration JavaScript error when selecting web content

• Type: Bug
• Status: Closed
• Resolution: Fixed
• Affects Version/s: 6.2.X EE, 7.0.0 M3
• Fix Version/s: 6.2.3 CE GA4, 6.2.X EE, 7.0.0 M2
• Component/s: Frontend Infrastructure
• Labels:
  • liferay-fixpack-misc-9-6210
• Branch Version/s:
  6.2.x
• Backported to Branch:
  Committed
• Story Points: 6
• Fix Priority: 3
• Git Pull Request: https://github.com/brianchandotcom/liferay-portal/pull/21568

1. Add the RSS portlet.
2. Click the cog icon -> Configuration
3. Click 'Select' under 'Header Web Content'

Expected result:
No JS error occurs.

Actual result:
JS error occurs: Uncaught TypeError: Cannot read property 'all' of null