Some states are sending out mail-in ballot applications (not ballots themselves) to registered voters. In other states, which have had mail-in voting only for 20+ years, the ballots themselves are sent out to the registered voters.
In Pennsylvania, you have to request a ballot either online or in person.
I requested my ballot a long time ago, and it will be in my mailbox in a day or two. However, I'm thinking I may not use it. The Trumpster is going to look at the results of the in-person balloting ONLY on election day (November 3) which, according to the surveys I've seen, will lean heavily Republican. (Republicans are the "I don't need a friggin' mask; I have my FREEDOM; so I'm gonna spread the virus and vote in person!!!" Democrats are the "Well, if I can vote safely without standing in line for 2 or more hours and not have to stand near Covidiots and mask holes, why not send in my ballot by mail?")
So... I think I might just put on my N-95 mask, my face shield, take a folding chair and my Kindle, and vote in person, just to keep the results a tiny bit less Republican on November 3.
On the other hand, I might just send it in and not worry about the Trumpster fire that will happen no matter what I do.