What I want to know is, is how do I get Gimp 2.2.7 to alter an image's
dimensions like that?
Activate the chain symbol in the layers dialog for all
layers (only necessary if there is more than one layer) - if
you don't "chain" them, only the active layer will be scaled.
Then use the "Scale Layer or Selection" tool from the
toolbox and drag the image border (or is it a layer border?
- not sure).
When finished with scaling, right-click the image, then
click image - fit canvas to layers to re-fit the canvas.
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