AutomaticCanvasSize sizes the negative Y axis

Kinda weird title right? Again…
So, trying to make my custom chat system, yk, “stack”:
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Using AutomaticCanvasSize in the Y axis:
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It should size upwards (the messages start at the bottom) but the canvas is sized towards the other end. Can’t figure out why.

For that, I was using UIListLayout:
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Eh, thanks.