Variable: font-lock-support-mode
font-lock-support-mode is a variable defined in font-lock.el.gz.
Value
jit-lock-mode
Documentation
Support mode for Font Lock mode.
If nil, means support for Font Lock mode is never performed. This can be useful for debugging.
The value of this variable is used when Font Lock mode is turned on.
Probably introduced at or before Emacs version 19.32.
Source Code
;; Defined in /usr/src/emacs/lisp/font-lock.el.gz
;;; Font Lock Support mode.
(defvar font-lock-support-mode #'jit-lock-mode
"Support mode for Font Lock mode.
If nil, means support for Font Lock mode is never performed.
This can be useful for debugging.
The value of this variable is used when Font Lock mode is turned on.")