Is there a good way to step away from an online political argument?

I've noticed that even after trying to wrap things up, like summarizing my point or saying "I'll leave it there", the conversation often keeps going. The thread keeps extending and it feels hard to actually bring things to a close.

I know that some people avoid online arguments altogether, but I do end up engaging sometimes.

So I'm curious: once you're already in it, is there a way to exit the conversation more cleanly, or does it basically come down to stepping away and letting the other person have the last word?