#IfWinActive, ahk_class MozillaWindowClass
XButton1::
    Send, {Z down}
    Sleep 20
    Send, {Z up}
    return
XButton2::
    Send, {Y down}
    Sleep 20
    Send, {Y up}
    return


#IfWinExist, ahk_class LWJGL
Loop
{
    MsgBox, hello
    Sleep, 2000
    ControlSend, , NumpadAdd, Minecraft 1.7.10
}