in Code.gs [187:197]
function clearNotes() {
var sheet = SpreadsheetApp.getActiveSheet();
var notes_range = sheet.getRange(1, 1, sheet.getMaxRows(), sheet.getMaxColumns()).getNotes();
for(var r in notes_range) {
for(var c in notes_range[r]) {
if(notes_range[r][c] && notes_range[r][c].indexOf('~SpreadsheetToES') >= 0) {
sheet.getRange(1+parseInt(r),1+parseInt(c)).clearNote()
}
}
}
}