Thank you sir, I was curious if you will get a “this browser/app is already installed” block? I don’t remember if windows does this or not when you try to install the same app twice.
Other than the Registry (as I mentioned above), of course you have to install twice, into two distinct locations on the disk volume (C:), or ideally on different volumes (like one on C: and the other on D:). I don't know if it would complain about "already installed" -- that's probably a function of the Registry keys, and whatever data the browser puts there.
You -might- get away with installing two different releases of the same browser. For example, it's possible to install different releases of Java JDK/JRE software side by side.