And for future reference:
To make a 32x24 icon (which is really only 24 wide with padding) into 24x24, use this (and adjust accordingly for other dimensions):
convert -background none -extent 32x32 -page -5+0 INFILE.svg - | convert -background none -crop 24x24 - OUTFILE.svg
And for future reference:
To make a 32x24 icon (which is really only 24 wide with padding) into 24x24, use this (and adjust accordingly for other dimensions):
convert -background none -extent 32x32 -page -5+0 INFILE.svg - | convert -background none -crop 24x24 - OUTFILE.svg