hi @kivaniutenko  thanks for reaching out.

Databricks alerts still support basic HTML in email templates, but HTML will render correctly only for email destinations and only with simple, allowed tags.​​

Quick things to try

• Make sure you are using Alerts v2 not legacy alerts.
• Check that the alert is still sending to an email address, not just a webhook or other integration where the content is handled as plain text. 
• Start by temporarily setting the default template to confirm HTML is properly rendered even with this config.
• Then change it to custom and start with a very simple body like: <p>Test <b>alert</b></p> and remove any complex HTML or CSS, then keep adding more. I tested with the static example you provided, which contains allowed tags without double encoding (< or >), and it worked as expected.​
• If even that simple HTML shows as text, I'd suggest opening a Databricks support ticket in the help center and sharing an example alert for further review.

I hope this helps, please let us know if it does.