Z:gnu-www-ja-free-digital-society--3014bc-But if you have a free program/en

But if you have a free program that handles a certain format, ipso facto that format is not secret. This kind of malicious feature can only exist in a nonfree program. Surveillance features, well, theoretically they could exist in a free program but you don't find them happening. Because the users would fix it, you see. The users wouldn't like this, so they would fix it.