To set a font size that isn't in the list, do the following:
1. Select the text you want to change and choose a font size from the list.
2. Click the angle brackets to open the editing window.
3. Open the search box (Ctrl+F), enter the current font size, and find it.
4. Replace the found number with the desired font size on the required rows.
5. Click Save in the window that appears, and then save the document.