--- a/.emacs-my	Sun Nov 01 15:05:04 2020 +0200
+++ b/.emacs-my	Mon Nov 16 00:32:43 2020 +0200
@@ -2575,6 +2575,8 @@
 
 ;; Since 27.1 it is enabled during font-lock. Need to disable explicitly.
 (setq diff-refine nil)
+;; https://emacs.stackexchange.com/questions/61760/lags-when-navigating-vc-root-diff-buffer/
+(setq diff-font-lock-syntax 'hunk-only)
 
 (when (and window-system (< emacs-major-version 26))
   (my--eval-after-load diff-mode