When doing floodfill, I get the correct result with png output, but not with gif.
Original Image:
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PNG Results:
convert christmas-black-and-white.gif -bordercolor white -border 10x10 -fuzz 1% -fill none \
-draw "matte 0,0 floodfill" -shave 10x10 christmas-black-and-white_trans1.png
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convert christmas-black-and-white.gif -bordercolor white -border 10x10 \
-alpha set -channel rgba -fuzz 1% -fill none \
-floodfill +0+0 white -shave 10x10 christmas-black-and-white_trans2.png
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GIF Results:
convert christmas-black-and-white.gif -bordercolor white -border 10x10 -fuzz 1% -fill none \
-draw "matte 0,0 floodfill" -shave 10x10 christmas-black-and-white_trans1.gif

convert christmas-black-and-white.gif -bordercolor white -border 10x10 \
-alpha set -channel rgba -fuzz 1% -fill none \
-floodfill +0+0 white -shave 10x10 christmas-black-and-white_trans2.gif
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