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Team based projects (NextGen) is not supported. This is due to that there is no way at the moment to hook into those projectsStatus colour Yellow title Waiting for atlassian platform support Old Issue View is not supported, due to that there is no hook at the moment. Use the new view to use the tool (https://support.atlassian.com/jira-service-management-cloud/docs/changes-to-requests-in-the-new-issue-view/)
Setting an invalid value as Default value on a Protected field that has Global context may prohibit issue creation for all projects not having the field on its create screen.
Make sure to to use Context to limit the field to the projects using it.
Make sure to use the correct format on the input value if using default value, specified here Protected Field Types
Agile Card - Field value shows encrypted value on card. (Works with unencrypted fields)Status colour Yellow title Waiting for atlassian platform support 
Export to CSV or Excel - when exporting as CVS or Excel the encrypted values comes out as encrypted strings.Status colour Yellow title Waiting for atlassian platform support
Importing values into encrypted field is not yet supported, use the API as workaround. Importing into unencrypted is supported for type text.Status colour Yellow title Waiting for atlassian platform support
Filter / Search view - Encrypted values will be displayed as an “View is not supported“, hence not searchable yet.Status colour Yellow title Waiting for atlassian platform support Can Protected Fields secure other vendors fields? No, the nature of the Atlassian cloud prohibits apps to interfere or override behaviors of other apps and core functionality. Only known extension points from app vendors can we used, these are very limited today. Each app also renders as a iFrame inside Atlassian cloud which makes them isolated.
Protected Fields is hidden on a Request Type on the Customer Portal in Jira Service Management - Today Atlassian Forge framework does not allow vendors to show fields on the customer portal yet
Forms (new) feature is not yet supported.
“Log in as” in the administration of Atlassian it is possible to login as another user if you are an admin. Protected field can not recognize the “Logged in as user” when running the session. The result will be that it treats the session as the current user instead and all permission will be based on that.
Bulk Edit values does not show in select boxes until a issue has one of the values, When trying to perform bulk edit on issues that does not yet have any PF values then the bulk edit shows a blank drop-down. As soon as one issue has a PF value the dropdown will be populated and bulk edit will work.