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Go to the apps setting (Settings → Apps)
Go to the “Secure Custom Fields“ setting page. Then, click the “Configure“ link for the field you want to configure permission.
Click the “Configure“ link for the field context you want to configure permission.
Add users, groups and project roles, and so on to view and edit permission. You can check “Grant to Any User” if you grant the permission to anyone.
Note: Users also need view permission to edit the field.
