Microsoft hides file extensions in Windows by default even though it's a security risk that is commonly abused by phishing emails and malware distributors to trick people into opening malicious files.

Microsoft has added a feature on the File Explorer Options or Folder Options ribbon and a Windows mini window, allowing the user to enable or disable the file extensions’ visibility in the File ...

I use my Mac in a multi OS environment (i.e. with Windows) and whenever I take a screenshot (Cmd-Shift-4) intended for a PC user, I have to go to information and tell the OS not to hide the extension ...