In Leads Module, I dont see Lead Owner "field update" as a workflow rule trigger option in my zoho crmplus. Only options are "is", "is not", "contains", "does not contain", "is empty", "is not empty". I need to automate an email notification action to trigger when a lead owner is assigned or changed, on create or edit.

When I search online for a solution, I get links directing me to select "field update" as a trigger. What am I missing here? Thanks in advance.