diff --git a/sdk_container/src/third_party/portage-stable/eclass/elisp-common.eclass b/sdk_container/src/third_party/portage-stable/eclass/elisp-common.eclass
index 117544e94b..654b302bb3 100644
--- a/sdk_container/src/third_party/portage-stable/eclass/elisp-common.eclass
+++ b/sdk_container/src/third_party/portage-stable/eclass/elisp-common.eclass
@@ -1,4 +1,4 @@
-# Copyright 1999-2024 Gentoo Authors
+# Copyright 1999-2025 Gentoo Authors
 # Distributed under the terms of the GNU General Public License v2
 
 # @ECLASS: elisp-common.eclass
@@ -626,12 +626,12 @@ elisp-modules-install() {
 
 elisp-site-file-install() {
 	local sf="${1##*/}" my_pn="${2:-${PN}}" modules ret
-	local add_header="1 {
-		# Find first non-empty line
-		:x; /^\$/ { n; bx; }
-		# Insert a header, unless we already look at one
-		/^;.*${PN}/I! s/^/;;; ${PN} site-lisp configuration\n\n/
-		1 s/^/\n/
+	local add_header="0,/\S/ {
+		# Delete any leading blank lines
+		/\S/! d
+		# Insert a header, unless we are already looking at one
+		/^;.*${PN}/I! \
+			i ;;; ${PN} site-lisp configuration  -*-lexical-binding:t-*-\n
 	}"
 
 	[[ ${sf} == [0-9][0-9]*-gentoo*.el ]] \
@@ -711,11 +711,15 @@ elisp-site-regen() {
 	;; DO NOT EDIT THIS FILE
 
 	;;; Code:
-	EOF
-	# Use sed instead of cat here, since files may miss a trailing newline.
-	sed '$q' "${sflist[@]}" </dev/null >>"${T}"/site-gentoo.el || ret=$?
-	cat <<-EOF >>"${T}"/site-gentoo.el || ret=$?
 
+	EOF
+	# Concatenate all site initialisation files.
+	# 1{/^;/s/\s*-\*-.*-\*-//} deletes file-local-var cookies from line 1.
+	# /\S/,$!d deletes any leading blank lines.
+	# $G inserts a blank line after each file.
+	sed -s '1{/^;/s/\s*-\*-.*-\*-//};/\S/,$!d;$G' "${sflist[@]}" \
+		</dev/null >>"${T}"/site-gentoo.el || ret=$?
+	cat <<-EOF >>"${T}"/site-gentoo.el || ret=$?
 	${page}
 	(provide 'site-gentoo)