* lisp/frameset.el (frameset-persistent-filter-alist):
Add :never filter for `font-backend'.
(client . :never)
(delete-before . :never)
(font . frameset-filter-font-param)
+ ;; Don't save font-backend because we cannot guarantee the new
+ ;; session will support the saved backend anyway. (Bug#38442)
+ (font-backend . :never)
(foreground-color . frameset-filter-sanitize-color)
(frameset--text-pixel-height . :save)
(frameset--text-pixel-width . :save)