Watching a couple of presentations today, it struck me that a lot of people apparently have developed "wavy red underline blindness".
Even screenshots of windows with text included the "you've probably spelled this wrong"-markings, and nobody even raised an eyebrow!
It is always the first thing I turn off in browsers, word processors and everywhere else I encounter it.
Not [only] because I'm excellent at spelling, but because the false positive rate of spelling mistakes is waaay too high for the markings to be useful.
Bonus tip: to spell check the current word in