Admin Theme in component configuration is missing thumbnail

• Type: Regression Bug
• Status: Closed
• Resolution: Fixed
• Affects Version/s: 7.0.0 Beta 1
• Fix Version/s: 7.0.0 DXP SP1, 7.0.3 CE GA4, Master
• Component/s: App Management, App Management > Plugins Configuration, Liferay Themes, ~ [Archived] Themes Infrastructure
• Labels:
  • liferay-digital-enterprise-70-sp1
  • liferay-fixpack-de-5-7010
• Branch Version/s:
  7.0.x
• Backported to Branch:
  Committed
• Fix Priority: 4
• Git Pull Request: https://github.com/brianchandotcom/liferay-portal/pull/43359

Admin Theme is missing thumbnail (please see screenshot)

Steps to reproduce:

1. Navigate to Control Panel > Configuration > Components
2. Click on Themes
3. Assert missing Thumbnail for the Admin Theme