A blinking one-pixel-wide bar is OK, when in focus. What drives me nuts is a blinking block like in consoles or Emacs: to me it's jumping up and down shouting "

A blinking one-pixel-wide bar is OK, when in focus. What drives me nuts is a blinking block like in consoles or Emacs: to me it's jumping up and down shouting "look at me, look at me!", and I came up with that description completely independently of breadbox here.