Support templates are a form, not ten emails
What a support desk repeats is not the whole letter.
It is structure: greeting, identity check, reason, next step, signature. Ten emails that differ only by name will rot the library in a quarter.
Change the greeting once. Every template that includes it changes. That is a template.

Split the structure
Shared blocks are small snippets, nested in the body:
%s:cs-hello%
%filltext&name=name%, regarding ticket %filltext&name=ticket%:
%fillarea&name=reason and handling%
Priority: %fillmenu&name=priority&opt=high&opt=medium&opt=low%
%fillcheck&name=urgent line&default=Please prioritize this ticket.%
%s:cs-sign%Change %s:cs-hello% once; every template that includes it changes. Nesting is documented in FillIn.
Which field
| What changes | Use |
|---|---|
| Name, ticket id, short number | Single line %filltext% |
| Reason, write-up, return notes | Multiline %fillarea% |
| Small closed set (priority, channel) | Menu %fillmenu% with &opt= |
| A sentence that is sometimes present | Optional %fillcheck% |
| Mutually exclusive paragraphs | Conditional %fillswitch% |
Do not use โedit hereโ as a variable. The popup appears on expand; confirm with โ/Ctrl+Enter.
Where it may fire
If the same replies are needed in the ticket tool, mail, and IM, keep the group global. If it wrecks the terminal, turn on ExpandIn for the support group and leave only the browser and mail client.
Sharing one pack of replies with coworkers is organization shared groups, not mailing around a document. See Shared groups.
Next: Abbreviation hygiene.