Selected image is modified just moving the pivot point in certain positions

[Gasparoken]

Steps to reproduce it:
1- Select a drawn area.
2- Visibilize Pivot Point.
3- Move the Pivot Point until the image is modified.

test.mov

Aseprite and System version

• Aseprite version: 1.3rc4
• System: macOS

[dacap]

It looks like the problem only appears when the pivot has negative coordinates and there is no rotation (if we rotate the image or skew it, the problem doesn't appear). And it's correct that it appears in some specific zoom levels.