The Brief: FTFY is an abbreviation for "fixed that for you."

DEEP DIVE
Popular on Reddit and Twitter, the acronym FTFY means “fixed that for you.” While it can be used as a sincere way to be helpful, it’s more often meant to sarcastically correct someone or share an opposing opinion.
On Twitter, people will reply to a tweet that they disagree with, rephrasing it to have a different meaning, and signing off with “FTFY.” On Reddit, it may be used as a sly remark in comment threads.
What the hell is the state of <every Bethesda game ever>, and why does it still cost so much?
FTFY— Opalium (@TheOpalium) July 4, 2020
"i refuse to live in fear" –> "i refuse to respect anyone's life besides my own"
"people need to live their lives" –> "people's lives are expendable for my own enjoyment"
ftfy π
— dusty rose (@rosapolverosa) July 2, 2020