Hi,

for other way round use this

I assume user has valid READ ACL to see the comments on both the forms

After update BR on sc_req_item table

Condition: Comments changes

Script:

(function executeRule(current, previous /*null when async*/) {

    // Add your code here

var appr = new GlideRecord('sysapproval_approver');
appr.addQuery('sysapproval',current.sys_id);
appr.query();
if(appr.next()){
appr.comments = current.comments.getJournalEntry(1);
appr.update();
}

})(current, previous);

Regards
Ankur