I am aware of this very similar question but I can't wrap my head around my corner case. In my situation, I need run those jQuery plugins unconditionally as I can't narrow down the potentially affected DOM nodes. My old code looked like this:
Template.Main.rendered = function() {
jQuery('time.timeago').timeago();
}
But with the new layout engine the rendered events won't "bubble up" to my Main template which means that timestamps won't be updated to human readable representations.