The file format has stayed the same in Office 97 > 2000 > XP (2002) > 2003 That is 10 years where 4 different versions can read the other version files without add-ins.

Windows can do by using the RunAs option / command.

Create a user and give them ACL access to the Mozilla program folder. You can then run Mozilla as the locked down user by right-clicking on the exe and choosing the "RunAs..." option OR you can create a shortcut using the command below...

Example:

runas /user:LockedDownUserName "mozilla.exe"

It will then prompt you for the password for that user. In fact, Microsoft didn't even allow the password as a parameter lest users get used to that and end up leaving the password exposed in unsecure batch files/shortcuts.

This isn't utilized as much b/c of 2 reasons:
1. Many applications are written with the assumption that they have Admin or Power User permissions - this requires developer training

2. This makes it more difficult to use your computer from an end-user standpoint. They don't even understand the concept of Admin/root, never mind additional levels of security.