Gifcam actually appears to have the same problem that Liceecap has, which is that you have to have the position the window to set the recording area. It's really annoying trying to move a window to line up perfectly with another one.
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Generally, you'd want to take a small portion of the screen for your GIFs so you can make out details and keep file sizes low, I think. If you need to perfectly capture a small gameplay window, you probably should go with OBS to record the window, and then use GIMP to export a GIF from that captured vid.