This patch modifies the key handing so that you can chain multiple bindings together like in sxhkd. After pressing Mod + ChainKey the next key press will be matched against any KEY in the keys array which is part of the Mod + ChainKey group and execute its function. If there isn't any match the key press will be consumed without any effect. This allows you group certain bindings together which all starts with the specified Mod + ChainKey prefix.