Html Codes in Customer Confirmation Mail

I can not use html tags in customer confirmation mail in customer.php language file, is there another easy way to make it happen, but html extension?

You did not mention what kind of problem you are facing exactly. what HTML tags did you try to save in the customer.php file? Please share more detail so we can help you.
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<b> </b> tags do not work in customer confirmation mail, i used in language/customer.php. version 2,3,0,2. send it as a plain text, also tried strong ,font bold, span. none of them is working.

Yes, there are other ways to include HTML formatting in customer confirmation emails without using HTML tags in the customer.php language file. One option is to use a template system that allows for HTML formatting, such as Smarty or Twig. Another option is to use a third-party email service that supports HTML formatting, such as Mailchimp or SendGrid, and then provide the formatted content in the email body.