App behavior: Deploying ClosePlan is blocked - Static Resources issue.

Deploying a ClosePlan is blocked.

Or

Graphics not displaying correctly (e.g. boxes displaying instead of Checkmarks on User Manager...)

 

Error Message:
Uncaught Error in $A.getCallback() [Cannot read property ‘getDescriptor’ of undefined]
Callback failed: apex://UserLicenseCheck/ACTION$checkUserLicense.

Location:
First go to User Manager to check the license assignment. The page may be blank and/or have display issues as seen above.

The Reason for this error / conflict is that there is a Salesforce update that blocks resources and cause icons to stop displaying. Salesforce is aware of this conflict.

Solution:
Gear Icon > Setup - enter 'Release Updates' and under the 'Archived' tab, look for "Enable Secure Static Resources for Lightning Components"
Click on 'View Update', disable the update and check to ensure that the issue is resolved.

 

Note:
The ‘Don’t enable it.’ Message is from Salesforce, they are aware of the issue.

Disabling the ‘Enable Secure Static Resources for Lightning Components’ will have no effect on your SFDC.