Isolate date -j -f ... + ... from locale.
Filed upstream as Issue #591 <https://github.com/OpenVPN/easy-rsa/issues/591>

--- easyrsa.orig	2022-05-19 01:53:50 UTC
+++ easyrsa
@@ -2037,7 +2037,7 @@ renewable() {
 	verify_ca_init
 
 	in_dir="$EASYRSA_PKI"
-	MATCH=$(echo "$*" | sed -re 's/\s+/|/g')
+	MATCH=$(echo "$*" | sed -re 's/[[:space:]]+/|/g')
 	DATE=$(date --date \
                "+${EASYRSA_CERT_RENEW} days" \
                +"%y%m%d%H%M%S")
@@ -2445,7 +2445,7 @@ display_san() {
 
 	if echo "$EASYRSA_EXTRA_EXTS" | grep -q subjectAltName; then
 		print "$(echo "$EASYRSA_EXTRA_EXTS" | grep subjectAltName |
-			sed 's/^\s*subjectAltName\s*=\s*//')"
+			sed 's/^[[:space:]]*subjectAltName[[:space:]]*=[[:space:]]*//')"
 	else
 		san="$(
 		x509v3san="X509v3 Subject Alternative Name:"
@@ -3828,6 +3828,8 @@ VERSION_TEXT
 
 NL='
 '
+
+LC_TIME=C ; export LC_TIME ; unset LC_ALL
 
 # Be secure with a restrictive umask
 [ -z "$EASYRSA_NO_UMASK" ] && umask "${EASYRSA_UMASK:-077}"
