Removing a background colour from an animated GIF was one of my tasks recently, and not having a clue how to do this, I spent a bit of time looking into it.
This is what I had to do:
From this 
to this 
I had to remove the green background and make it transparent.
It is easy enough if I wanted to pay someone to do it, but I wanted to try to learn myself.
In the end I didn’t learn, but I did find a good website that I ended up using to do it nice and easily. GifMagic has an online facility that can do exactly that, PLUS more, and it is FREE.
For a simple job like that, there seemed no point in buying a program for it, although at some stage, if I want to get something more complex, I may well begin looking at the other options for GIF Makers.
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