e72afa9dbf replaced nil, which is invalid as a face definition,
with ((t (:inherit default))), but that does not actually result in
an "empty" face, which doesn't set any attributes. Instead it doubles
down on all attributes set for the default face. Replace that with
((t)), which accomplishes what appears to have been the intention.
* lisp/net/shr.el (shr-h4, shr-h5, shr-h6):
* lisp/nxml/nxml-mode.el (nxml-text):
* lisp/progmodes/make-mode.el (makefile-shell): Use empty face
definition ((t)), instead of ((t (:inherit default))).
800a272b62