2
I'm not a Smarty expert, but when I see a '
db:' in front of a template, I think it means it is accessing a source from the DB.
Try going into the DB, look at xoops_tplfile table, check the tpl_id of the template mentioned above, then look at the HTML code of that template in xoops_tplsource table using the tpl_id as reference.
Just in case I was wrong in my assumptions, could you specify the file you were editing when this happened?