I wrote a bug report on this because it took a while to figure out the cause of the problem, but now that I know what's going on it looks more like a strange design choice. In the menu for a sprite, there's an icon under "Image:" and "Size:", right next to the width and height of the sprite. What the icon does depends on whether the sprite editor tab for that sprite is open: -If the sprite editor tab is open, the icon brings up the "Resize All Frames" window (which only allows resizing the canvas), and pulls up the sprite editor tab. -If the sprite editor tab is NOT open, the icon brings up the "Resize Properties: (name of sprite)" window, which allows BOTH resizing the canvas and scaling the image (and appears to be the only way to scale the image). In no circumstance would the "Resize All Frames" window be preferred, and the way to get to the "Resize Properties" is not intuitive since both windows use the same button.