Subject: bug#76983: NS redisplays itself constantly

From: Daniel Colascione <[email-masked]>
Date: Wed, 12 Mar 2025 11:28:04 -0700

NS is redisplaying itself several times per second even when nothing is
happening. I've tried disabling every timer and stopping every
process. I've also seen a scenario in which NS redisplays itself several
hundred times per second, burning a CPU core (while being responsive).

emacs -Q

(progn
  (blink-cursor-mode 0)
  (defvar redisplay-count 0)
  (defun probe-redisplay (&rest _) (incf redisplay-count))
  (add-to-list 'pre-redisplay-functions #'probe-redisplay))

eval redisplay-count once in a while