Expect jagged edges, since gif format doesn't support partial transparency: it's either "off" or "on" for each pixel.
>>616536Gimp can edit animations, you don't need to separate the frames. Relevant tools:
"Filters>animation" menu
you'll probably need to "unoptimize" before you start editing, and "optimize" it again afterward. Also "playback" is useful.
"Image>mode" menu
gifs are supposed to be "indexed", meaning they have fewer colors, but some things (like resizing) work better in "RGB" mode.
"Layers"
the eye-shaped icon turns frames off and on.
the layer name can optionally include bits like "(300ms) (replace)" or "(90ms) (combine)" which sets the timing and whether you want the playback to clear the image with each step or draw on top of the last frame. Don't obsess over this until you're finished editing, though, as some filters will change the labels and you can set default values for everything when you save as gif.
