Dead easy in GIMPAll the frames appear as layers, and you just erase the unchanging parts of each layer.
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Albert the Mildly Deranged purveyors of nothing much since a year or two ago,
Mon 1 May 2006, 20:21,
archived)
hmmmmI will have to take a look at this GIMP
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We are the lemon irked your craw on,
Mon 1 May 2006, 20:53,
archived)