It happened with your permission as has been explained many times.
You wrote this often, Eddy. And it's always wrong.
Nobody expects a totally new program like a browser when updating his security software.Maybe SafeZone Browser is a helpful program, maybe not. I just begin to play with it. And it doesn't work as it should. FAQ "SafeZone browser .. is automatically opened in a Shielded window to prevent any threats from reaching your browser or PC" is wrong, at least for MY banking accounts. Avast shout alter this text and tell people that only known banks are protected.
But this remains: The company whose virus security software I must trust does something to my computer without my knowledge. And so without any authorization. And this is NOT a legal problem, so let us better talk about the facts:
I must trust Avast. I must be certain that everything they do deep inside my operating system helps my against malware, nothing else. And I must be certain that nothing else changes without my knowledge. And it is no wonder that some users discuss to change their virus software.
In the past Avast had troubles with unwanted advertising in the free version. That was nothing compared to that what's going on here now.
I hope that this company finally begins to understand their users, paying as well as free users.
stibi