- Resize handles snap to the canvas, other layers and guides, as moving does.
- Values typed or dragged in the Move bar's X, Y, W, H, Scale and rotation fields apply straight away, with no Apply, as one undo step.
- Clone Stamp and Blur keep a scaled-down layer's full detail, so it stays sharp when scaled back up.
- Layer masks work like Photoshop's: with a selection, Add Layer Mask reveals it (Option-click for the opposite), and Option-clicking a mask thumbnail shows the mask on its own.
- Ungroup Layers (⇧⌘G), also in a folder's right-click menu.
- Tabs can be dragged to reorder, and ones that don't fit gather under a menu.
- Holding Command flips Auto Select either way while it's held.
- A brush that can't paint now says why, and Select All then Inverse deselects.
- Scaled layers show their scale in the Layers panel, and Cancel and Apply only appear when an edit is waiting for them.
Thanks to @cheyras for several of these.