Downloaded Files Won't Work Because of Browser

I am not using the Avast SafeZone Browser, I instead use Firefox. I attempted to download LibreOffice a few weeks ago, and for some reason after clicking on the downloaded file, it opened up the Avast browser and then it proceeded to automatically download again, giving me two copies of the same file. If I then try to open up those files, it does the same thing. I tried opening them in Internet Explorer, but that didn’t work for some reason and it opened up Avast SafeZone and did the same thing, downloading the file which again will only lead to the SafeZone downloading the file again. I end up with a bunch of files (which when I delete them say they contain ‘0’ bytes).

Downloading images work fine, but documents and other files so far do not.I contemplated deleting SafeZone but I like the features and feel it may come in handy on different occasions. So I wanted to ask why exactly is it doing this and how do I fix it?

EDIT: As a side note/question, I went to my control panel and found that Avast SafeZone Browser to uninstall it, and its not even listed. Why is that?

In order to uninstall the SafeZone Browser go to the control panel, right click on Avast, change, modify, untick the SafeZone Browser, then reboot your computer.