Ajax indicator no longer works & results in warning in console.

Steps to reproduce:-->
1.Login to CMS on http://cms.demo.test.onehippo.com/?1 or start Gogreen enterprise project.
2.Check in the console.
Below warning is logged.
[INFO] [talledLocalContainer] 29.06 10:44:51 WARN [ResourceReferenceRegistry.java:359] A ResourceReference wont be created for a resource with key [s
cope: org.hippoecm.frontend.skin.Icon; name: images/loader/ajax-loader.png@2x.64px; locale: null; style: null; variation: null] because it cannot be l
ocated.

3.Check in browser console below warning is logged.
Failed to load resource:
http://cms.demo.test.onehippo.com/wicket/resource/org.hippoecm.frontend.skin.Icon/images/loader/ajax-loader.png@2x.64px
the server responded with a status of 404 (Not Found)

4. Indicator is no longer visible when the perspective gets switched or any activity is performed in cms.