Complex software is possible to get right in the same sense that it is possible for all the O2 molecules in this room to move to the other side of this room at the same time.<p>It is technically possible, but improbable enough that, in the absence of direct evidence to the contrary (in this case, a functional browser that <i>doesn&#x27;t</i> have bunches and bunches of exploitable bugs in its JS engine), it may as well not be.