I am 100% convinced this is what is going to happen. Election Night will be a Trump landslide. But the media will refuse to call it for him, no matter what, because of the "pending" mail-in vote.
Over the course of the next weeks and months, Dems will find whatever amount of votes they need to flip the election for them. If they need 3 million, they'll find 3 million. If they need 5m, they'll find 5m. 10 million. Whatever number it takes, they'll oops find pallets of uncounted mail-in ballots in the parking lot.
What are we going to do then? What is Trump going to do? He's never one to back down from a fight. It's going to be absolute chaos if he declares the election illegitimate (which he should, if they try this). Is it finally going to Minecraft time?
Dems have an unironic political theory now called the "Red Mirage". Look it up. It's not just something we think could happen, they're actively preparing for this to be the case.