The underlying intent here (figure out if it's an existing customer of our locally installed apps when they visit our website) doesn't seem bad, but I certainly dislike both the hosts file and localhost detection options.
I'm curious if there's a "good" way to do this.
Just do it by asking users to log in. Am I missing something here ?
Next they'll be installing a font like TeamViewer did... https://community.teamviewer.com/English/discussion/124507/s...
I dislike the intent too. A website should simply not be able to see which apps I've got installed. Imagine Facebook doing stuff like this in order to know what ads they should serve.