Help
Show file extensions
Windows
To show file extenstions, open your file explorer and click on the View1 tab in the ribbon menu. In the group Show/hide1 tick the box named File name extensions1.
macOS
To show file extensions, open up a finder window. In the menu bar, click on Finder and then on Preferences1 (or press ⌘ Cmd,). Click on Advanced1. Tick the box next to Show all filename extensions1.
1The text/name may vary depending on your language