The Summary Test field type leverages existing functionality as the multi select field. You can convert that to a text field and it will be a semi colon delimited string.
The formula below would give the first of the maximum 25 Summary text elements, separated by a comma, which I suppose might work for many tracking websites.
var text value = [my summary text field]);
List(",",
Trim(Part($value,1,";")),
Trim(Part($value,2,";")),
Trim(Part($value,3,";")),
Trim(Part($value,4,";")),
Trim(Part($value,5,";")),
Trim(Part($value,6,";")),
Trim(Part($value,7,";")),
Trim(Part($value,8,";")),
Trim(Part($value,9,";")),
Trim(Part($value,10,";")),
Trim(Part($value,11,";")),
Trim(Part($value,12,";")),
Trim(Part($value,13,";")),
Trim(Part($value,14,";")),
Trim(Part($value,15,";")),
Trim(Part($value,16,";")),
Trim(Part($value,17,";")),
Trim(Part($value,18,";")),
Trim(Part($value,19,";")),
Trim(Part($value,20,";"))
)
or else you can just use the first Part to get the first entry.
Trim(Part($value,1,";"))
