We are aware of an issue where the script attributes for Entity references are not showing the Entity nor are accepting values.
The team is looking at this as an urgent issue and be releasing a fix as soon as we can.
Please follow this thread for updates
Also a related isssue:
We’ve isolated the issue and working on a fix.
Existing Entity reference attributes cannot be seen or changed but the value is retained. New Entity reference attribute cannot be set a value.
We’ve released a fix to the Editor that solves both of the above issues
Sorry to those that were impacted by these issues and we will investigate further onto how and why this had happened