Limitations of Global Field

You can add up to 400 fields within a Global field, which aligns with the maximum field limit per content type.
A single content type can include a maximum of 25 Global fields.
If a Global field is marked as Multiple, the total number of instances cannot exceed 100.
A Global field and a content type cannot share the same name.
You can nest Global fields up to 5 levels, including the parent field.
Labels are not supported in Global fields.
Field visibility rules cannot be applied to Global fields.
Only users with the Owner, Admin, or Developer role can create Global fields.

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