your / you’re
Two words. One is ownership, one is a contraction. You are mixing them.
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Wrong: Your going to love this.
Right: You’re going to love this.
“You are going to love this.” If that works, it’s you’re.
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Wrong: Is this you’re coffee?
Right: Is this your coffee?
The coffee belongs to you. Possession is your.
The test
Say “you are” in its place. Survives? You’re. Doesn’t? Your.
There is no third option and no edge case. This is the same test as they’re/their/there, and it works for the same reason: one of them is a contraction and contractions can always be expanded.
Autocorrect will not save you here. Both are real words spelled correctly, so nothing gets underlined and the mistake ships.
Now go check your last three messages.