Slice behavior change in Aseprite

Hi,

I used to be able to add a slice, and position it differently from one frame to another. This is very handy to create things like hitboxes. With the newest Aseprite (v1.3.18.1), if I create a new slice and try to do that, then the slice position seems to be shared across frames. Moving it on one frame moves it for all frames. If I modify an older slice (created with an older Aseprite), then it can still be positioned independently for each frame. So it’s like there’s a hidden slice configuration frame setting that triggers that different behavior (shared vs frame specific), and I can’t find it anywhere. Or maybe it’s a bug?

I’d appreciate any help.

Edit: I’ve also tried v1.3.17.2. Same behavior of slices being shared across frames. Sadly, I don’t think there’s a place where I can redownload older versions.