No I am on normal Windows 10 OS used for mining mainly. I transferred funds to another wallet immediately just to be safe and let only a very tiny amount of bitcoin, still good enough to make the hacker make a move if there is any (although I highly doubt it as this is the only PC I use electrum and no other person have access to it, is protected with Avira Internet Security all the time) but just to have peace of mind.
No I have no reason to reinstall, I am only surprised of such changes without notifications. I am in a wait and see mode although I am confident I am safe to the max extent.
Maybe you just forgot that you change your appearance from your electrum before.
This is the same what happen to me before but i install different installer electrum stand alone and windows installer i already had tbe electrum walle i don't remember but just forgot to uninstall first my old electrum and install standalone..
After that I import wallet.dat to my electrum and seen its set to mbtc showing so i change it to btc.. few days ago i made transactions and check the explorer but i redirected to blocktrail the same as you mention so i think you install a new electrum or update it or you just forgot that you changed appearances of your wallet..
Well for me my bitcoin still there and i think still safe.. since you had anti virus i think it would be safe..
For me i am always using kaspersky total security because they support cryptocurrency..
