Unable to parse script when trying to personalize Journey alerts

Summary:

Hi Team,

I have a customer requirement to include personalization which involves some HTML scripting. When I try to include the code(Groovy script+HTML) in source code editor and try to save it, it gives me a script parsing error. I have attached screenshots for the same. Could you please let me know if HTML scripting is possible in Checklist/Journeys Alerts

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