Merge from origin/emacs-28

08de838531 ; Improve commentary in the last change
3da9fa875b Make hieroglyphs display correctly with existing fonts
928e05f2d6 Clarify "default face attributes" in the ELisp manual
5dbb04e0eb Make `C-u RET' work again
d72fefdeab Fix typos in the manual and in a comment

lisp/language/misc-lang.el

@@ -192,7 +192,25 @@ thin (i.e. 1-dot width) space."
    composition-function-table
    #x13437
    (list (vector "\U00013437[\U00013000-\U0001343F]+"
-                 0 #'egyptian-shape-grouping))))
+                 0 #'egyptian-shape-grouping)))
+  ;; "Normal" hieroglyphs, for fonts that don't support the above
+  ;; controls, but do shape sequences of hieroglyphs without the
+  ;; controls.
+  ;; FIXME: As of late 2021, Egyptian Hieroglyph Format Controls are
+  ;; not yet supported in existing fonts and/or shaping engines, but
+  ;; some fonts do provide ligatures with which texts in Egyptian
+  ;; Hieroglyphs are correctly displayed.  If and when these format
+  ;; controls are supported, as described in section 11.4 "Egyptian
+  ;; Hieroglyphs" of the Unicode Standard, the five lines below (which
+  ;; allow composition of hieroglyphs without formatting controls
+  ;; around) can be removed, and the entry in etc/HELLO can be
+  ;; restored to:
+  ;; Egyptian Hieroglyphs (𓂋𓐰𓏤𓈖𓆎𓅓𓏏𓐰𓊖) 𓅓𓊵𓐰𓐷𓏏𓊪𓐸, 𓇍𓇋𓂻𓍘𓇋
+  (set-char-table-range
+   composition-function-table
+   '(#x13000 . #x1342E)
+   (list (vector "[\U00013000-\U0001342E]+"
+                 0 #'font-shape-gstring))))
 
 (provide 'misc-lang)