Nope, it is definitely 18x18. Some people use 20x20, but that is too big for some skins and the icon will end up being cropped. The default ones are 18x18.
Edit: The default width can be up to 25px. So the max default size is 25x18.
Yeah always add the config file before adding into game.. Im now just wondering if i should just start them all over again and replace the complete file see if that helps...
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