Copy in folder contents view is not working

Plone Support
1

I can not do a copy (and therefore paste) in folder_contents view in Plone ClassicUI 6.0.14, 6.0.15, and 6.1.1. After I select an item, the browser reports the following error in the console:

caught (in promise) ReferenceError: UID is not defined

Then, when I click on the copy icon, I get:

Failed to copy items: 1 could not be found

However, this issue is not in the demo site: Welcome to Plone — English

I get the error in a newly created instance with no other add-ons activated.

I have also tried running my test sites in debug and production modes but I get the same error. Anyone else experienced this or know what could be the issue?

Thanks.