Browsers different to IE or Edge providing the language setting of the browser to AWI and based on this the date format is used. Changing the workstation settings doesn't provide the result expected.. In my case Google Chrome.
With Browser chrome you have to open chrome://settings/languages and change the default from English (United States) to for example English. Therefore you have to choose the language and move it to the top in the list.
After this please logoff from AWI - optional restart your browser - and logon again. Now the format should be DD/MM/YYYY or in my case as my browser setting is German DD.MM.YYYY.