ScriptRunner Behaviours: Hidden issue types can still be selected by typing (Ex : Epic)

[jira_admin_cu]

We are using ScriptRunner Behaviours in Jira Data Center to hide the Epic issue type from the Issue Type dropdown for certain projects. While Epic is hidden from the list, users can still create Epics by manually typing “Epic” into the Issue Type field. Based on the documentation, it appears this is a limitation of Behaviours, as they control only the dropdown, not the type‑ahead search. Can someone confirm whether this behavior is expected and whether there is a supported way to prevent hidden issue types from appearing when typing and how to resolve that?

I used the script below as a scriptrunner behaviour script in an initializer, and I'm using it for 60+ Jira projects.

Please find the attached screenshots for your reference.

import com.atlassian.jira.component.ComponentAccessor

import com.atlassian.jira.security.roles.ProjectRoleManager

import com.onresolve.jira.groovy.user.FieldBehaviours

import groovy.transform.BaseScript

import static com.atlassian.jira.issue.IssueFieldConstants.ISSUE_TYPE

@BaseScript FieldBehaviours fieldBehaviours

def projectRoleManager = ComponentAccessor.getComponent(ProjectRoleManager)

def allIssueTypes = ComponentAccessor.constantsManager.allIssueTypeObjects

def user = ComponentAccessor.jiraAuthenticationContext.loggedInUser

def issueTypeField = getFieldById(ISSUE_TYPE)

def remoteUsersRoles = projectRoleManager.getProjectRoles(user, issueContext.projectObject)*.name

def availableIssueTypes = []

if ("Jira Security Role" in remoteUsersRoles) {

    availableIssueTypes.addAll(allIssueTypes.findAll { it.name in ["Epic","Enabler","Feature"] })

}

if ("Users" in remoteUsersRoles) {

    availableIssueTypes.addAll(allIssueTypes.findAll { it.name in ["Bug", "Defect", "Dependency", "Enhancement", "Spike", "Story", "Sub-task", "Support Request", "Task", "Customer Incident", "Troubleshoot Request", "Improvement", "Service Request","Tech Debt","Support"] })

}

issueTypeField.setFieldOptions(availableIssueTypes)