This is in diff-mode.el

(defface diff-changed
  '((((type tty pc) (class color) (background light))
     :foreground "magenta" :weight bold :slant italic)
    (((type tty pc) (class color) (background dark))
     :foreground "yellow" :weight bold :slant italic))
  "`diff-mode' face used to highlight changed lines."
  :group 'diff-mode)

Why does w32 get no fruit salad love?

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Le