Of all the downloads for Avast to block!- last supported browser for windows XP!

Recently, there used to be 2 browsers STILL!! updated for XP securitywise - both based on palemoon which is based on firefox.
Mypal - which for a few months now is no longer being updated each month - due to some legal or copyright issue(s).
& this last remaining one is still being updated EACH WEEK!! It’s called NEWMOON.
http://o.rthost.win/palemoon/?sort=date&order=desc
When i tried downloading Newmoon vers 28 32bit to ANOTHER XP computer, Avast Free told me(for the 1st time EVER on any download) that there was an issue, it stopped the download, & said it would take many HOURS to check it out!!! WTH.
I went into avast settings & for “Enable Cyber Capture” i temporarily changed it from “always block it” to “allow me to decide”. & was able to install the browser.
Why would this happen all of a sudden, considering all the other versions in that file (32bit) that NEVER gave me any problem when i installed them in the past?
Can i assume avast is later going to place a popup in the lower right of my screen notifying me of their findings?
BTW, NO ONE should be using firefox, chrome, etc. in windows xp - those browsers have not been updated for a few YEARS for windows XP!

NEVER MIND, AVAST JUST ALERTED ME WITH A POPUP THAT THE FILE IS FINE.
WHAT A RELIEF! I DO NOT WANT TO HAVE TO BUY A WINDOWS 10 PC RIGHT NOW, HOPING I CAN UPDATE IT TO WINDOWS 11, WHICH JUST CAME OUT THE OTHER DAY!