Questions about email template

Questions about email template

I'm facing a little issue with email templates, for invoices and/or estimates.

I've customized the email template and put a html code, however after saved it, Zoho changes my code automatically inside my html code with a lot of <br> tags (<br> is line-break in html) and the template gets broken with those line-breaks. Is it normal or I can't use html content for email templates?

Thank you.