Snap to Layout Grid doesn't work with off-pixel objects when dragging from the corner
When you grab the edge of a box, it snaps to the layout grid when resizing. However this doesn't work when you grab the corner handle.
I just was able to reproduce your issue, and it looks like an issue with off-pixel objects while dragging on the corner. Thanks for your feedback – I’ll pass this along to the team that owns this area.
Ah ok. This doesn't happen if the shape is aspect unlocked. It only happens when you lock the Width/Height aspect ratio. I've done a short video explaining the various situations.