I think stiff-fronted shirts were worn with day-dress in the late Victorian era. If you squint enough at a high quality photos from the era you can sometimes make out that characteristic flatness or a shirt stud. It definitely fell out of fashion post-Great War, most 'fashion dress code' charts and grids mention them with day-dress around the 10s and 20s, but they definitely became uncommon. You can also see men wearing pleated shirts with their summer day clothes sometimes.Darcy Clothing is also a good source. In the meantime, I have a question. When wearing Morning attire...i.e morning coat, striped trousers, etc. is it acceptable to wear a stiff, detachable wing collar and boiled-front shirt? I do prefer this look and there are many examples, photos etc . of gentlemen in the '30's and '40 's wearing Morning attire with the wing collar. Some folks say that it is now inappropriate and others say it is fine. May I kindly have the thoughts of the people on here ? Thank you !!