The 'Send Multiple Emails to Individual Recipients' checkbox ensures that when sending an email to multiple recipients, each recipient receives the email separately, without seeing the other recipients' email addresses. It is available on email editor/email client page, as shown below:

To set this checkbox as checked by default, follow the steps below:
Create a Custom Metadata Type:
'e2a_Customer_Settings' (you can customize the label as needed).Add a Custom Field to the Custom Metadata Type:
'e2a_Customer_Settings__mdt'.'Value' (customize the label and length as per your requirements).
Create a Setting Record for 'Send Multiple Emails to Individual Recipients':
'Send_Email_To_Individual_Recipients'.'true' to have the checkbox checked by default, or 'false' to leave it unchecked.
Yes, you can customize the labels and field names to suit your needs, as long as the functionality remains intact.
Once the setting is configured, you can manage it by navigating to Setup > Custom Metadata Types > e2a_Customer_Settings__mdt > Manage. Here, you can create, update, or delete records as needed.
Using Custom Metadata Types allows you to store and manage configuration settings at the application level. This approach provides flexibility and central control without requiring custom code, making it easier to maintain and update your settings across your Salesforce organization.
Yes, Salesforce recommends using Custom Metadata Types for settings like this. It provides a scalable and maintainable way to manage configurations within your Salesforce environment without modifying the underlying code.
Please contact us at support@ortooapps.com for any questions.