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any strange software on the same computer that I use for Bitcoin. I also generate my private keys on a old computer & printer that will never
see the internet again. I will melt it down myself.
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Large Bitcoin Collider being a rootkit makes more sense than it cracking private keys.
LBC is like distributed CPU mining. Even if they had a million people running it, I doubt it would do much with the (relatively) low amount of computational power at its disposal.