This is 100% correct. If you Google Image search for "gatekeeper warning" https://www.google.com/search?q=gatekeeper+warning&hl=en&tbo=u&tbm=isch&source=univ h

This is 100% correct. If you Google Image search for "gatekeeper warning" https://www.google.com/search?q=gatekeeper+warning&hl=en&tbo=u&tbm=isch&source=univ https://www.google.com/search?q=gatekeeper+warning&hl=en... all you see are dialogs telling you about unknown developers, or non-signed apps, or your settings keeping an application from being opened. I have never seen the dialog being showing in this blog post ... except for a single time: XProtect binary file detection, built into OS X for defense against a few known malware attacks out there. Pretty sure the reason that this "works" and that the author of the post is getting that dialog is that XProtect is getting a false positive on their Flash-based projects and signing the app either avoids XProtect (scary if true) or changes the signature enough that it doesn't register as a false positive any more.