Typos? Yeah! Anything else? Not at least is a horrible grammar mistake. If I stop to edit I won't make any progress, I'll just spend all my time overanalyzing every word

I do it when there's something that ruins the flow of the story to me. Like if there's a subplot or plot point I need in order for the ending to work, I'll restart and edit. But as long as the story is somewhat smooth, I'll keep going.