It&#x27;s very common to find mixed tabs and spaces where people use tabs. The first sign of this is inconsistent indentation. Maybe they&#x27;re just sloppy? Oh, hm, here&#x27;s some more code where it&#x27;s <i>wildly</i> inconsistent. Time to play guess-the-tab-width until it settles down. Now should I add a comment at the top to tell Emacs about this setting next time I open the file? Probably not, sigh.<p>Semantic tabs would be good with consistent culture and tooling behind them.