Users cannot access Skuid pages in Salesforce community or Force.com sites

One client on NA73, Spring '19 Patch 18.4, Skuid version 11.1.11., Sites

Developer org on NA46, Spring '19 Patch 18.4, Skuid version 12.0.11, Sites

Note that I also have a client on NA102, Spring '19 Patch 18.4, Skuid version 10.0.10 who is not affected by this issue.