So, even in normal times, a confession is invalid if one goes to a priest outside of his jurisdiction??
And what about going to an Orthodox priest in danger of death, etc?
Yes, in normal times, if a priest from, say, the Cleveland Diocese were in Chicago, say visiting family or on vacation, vs. say by invitation of the bishop of Chicago specifically to help out, outside of his own bishop's territory, he wouldn't be able to help out with Confessions until he went to the Chancery and obtained the necessary jurisdiction from the Bishop of Chicago. This is, BTW, where "common error" fits in. Let's say this priest didn't know this and just sat in the Confessional in a church in Chicago, and the faithful rightly just assumed he had the necessary jurisdiction, they start lining up and going to Confession, those Confessions would be valid due to the dispensation of the Church. If found out, I'm sure the priest would be reprimanded and required to do some refresher studies. "Common Error" is not, as the SSPX have long spun it, a reference to widespread doctrinal error, just as "Faith is greater than obedience" refers to obedience to positive commands, and not to the teaching authority of the Church, the Magisterium.
Of course, with emergencies, i.e. danger of death, any valid priest, Orthodox, schismatic, even laicized, would be able to validly hear the Confession due to the fact that the Church not only gives them the jurisdiction for that act, but even commands them to do so, for the good fo the faithful. St. Pius X permitted Catholics in Orthodox territories to receive the Sacraments, including Confession, from the schismatics ... and by that act he effectively gave the Orthodox the necessary jurisdiction, for those acts only, to hear the Confessions.
So the mind of the Church is always toward the souls of the faithful, and that is why it's said that the Supreme Law is the Salvation of Souls. Unless we're hallucinating, and all is right with the Conciliar Church, and there's on Crisis whatsoever, where there's "nothing to see here, move along", the Church supplies jurisdiction to Traditional Catholic priests for valid Confessions.