If set, the cursor is blinking.
See also select cursor style for a more widely supported alternative.
🛈 This mode is additive to blinking part of the select cursor style setting.
🛈 This mode is synchronized to the blinking part of the select cursor style setting.
🛈 xterm has user preferences to override/modify the effect of this mode, see read-only: user cursor blink setting and read-only: user cursor blink combination setting.