Cannot add a small image to a Template

• Type: Bug
• Status: Closed
• Resolution: Fixed
• Affects Version/s: 7.0.0 Beta 7
• Fix Version/s: 7.0.0 Beta 7
• Component/s: Dynamic Data Mapping, Dynamic Data Mapping > Template Editor
• Labels:
  • EXP7
• Fix Priority: 3
• Git Pull Request: https://github.com/brianchandotcom/liferay-portal/pull/35968

Steps to reproduce:

1. Begin to Add a Web Content Template
   • Expand the Details section
   • Flag Small Image
   • Upload a Small image file

Expected result:
The upload will work.

Actual result:
The upload (which works on WC articles) fails, giving the following cryptic reason:

"Your request failed to complete.
Image names must end with one of the following extensions: ."

See attached screenshot.