Take control of your customer communications with the Device Activation email template. You can use the template to customize the emails your users receive when they log in from an unfamiliar browser, app, or location.
Where: This change applies to Aura, LWR, and Visualforce sites accessed through Lightning Experience and Salesforce Classic in Enterprise, Performance, Unlimited, and Developer editions.
Tailor Device Activation Emails for Experience Cloud Sites (salesforce.com)