I have a five year old inexpensive rebuilt macbook air and it has been running fine but it does not seem to be successfully downloading the newest version of Firefox. I am attempting to manage my website and it keeps telling me to update my browser. Any suggestions? I am not really sure how many things or what things to look at to dtermine if this computer can handle the latest version. I am running Catalina 10.15.1 and my current firefox appears to be 64.0.2