A maze is right...but it doesn't end there - play with the contrast & color.
Whether I open the image in a new tab or save directly, Firefox's PassLoc still gives me the content. The online version operates just the same. DiffImg is showing the presence of a message compared to the original image, below.
Nope. Take this seemingly identical pic. You see them all the time on the net. But look at what's inside it. Add a password and there is your private space. Questions?