In an Add note field if I add the <style> tag like the image and click the Insert

then if I go again to the add note to edit something then the box is empty...I tried to click all the buttons (insert-edit HTML etc.) but nothing. Why this happens? If I want to have a style for example in a Add Note field (with <style> tags) then everytime I must delete the add note field and add a new one with the new style?