Hi,

There is no Short cut to figure out which script updated the work_notes.

you have to look all scripts (Workflows,BR,ScriptIncludes);

search with *work_notes of each component  in Script field and some filters on table and check every script.

if the message in work notes is hardcoded then you can directly search that message in script field and check out the results.

Hope that helps!

Regards,

Jagmeet