diff --git a/.github/workflows/PebbleStrict.yml b/.github/workflows/PebbleStrict.yml
index f7907d8b..c1ea1cd2 100644
--- a/.github/workflows/PebbleStrict.yml
+++ b/.github/workflows/PebbleStrict.yml
@@ -35,5 +35,28 @@ jobs:
       run: curl --request POST --data '{"ip":"10.30.50.1"}' http://localhost:8055/set-default-ipv4
     - name: Clone acmetest
       run: cd .. && git clone https://github.com/acmesh-official/acmetest.git  && cp -r acme.sh acmetest/
+    - name: Run acmetest
+      run: cd ../acmetest && ./letest.sh
+
+  PebbleStrict_IPCert:
+    runs-on: ubuntu-latest
+    env:
+      TestingDomain: 10.30.50.1
+      ACME_DIRECTORY: https://localhost:14000/dir
+      HTTPS_INSECURE: 1
+      Le_HTTPPort: 5002
+      Le_TLSPort: 5001
+      TEST_LOCAL: 1
+      TEST_CA: "Pebble Intermediate CA"
+      TEST_IPCERT: 1
+
+    steps:
+    - uses: actions/checkout@v2
+    - name: Install tools
+      run: sudo apt-get install -y socat
+    - name: Run Pebble
+      run: cd .. && curl https://raw.githubusercontent.com/letsencrypt/pebble/master/docker-compose.yml >docker-compose.yml && docker-compose up -d
+    - name: Clone acmetest
+      run: cd .. && git clone https://github.com/acmesh-official/acmetest.git  && cp -r acme.sh acmetest/
     - name: Run acmetest
       run: cd ../acmetest && ./letest.sh
\ No newline at end of file
diff --git a/Dockerfile b/Dockerfile
index c42f4f39..fb842c83 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -55,6 +55,7 @@ RUN for verb in help \
   deactivate-account \
   set-notify \
   set-default-ca \
+  set-default-chain \
   ; do \
     printf -- "%b" "#!/usr/bin/env sh\n/root/.acme.sh/acme.sh --${verb} --config-home /acme.sh \"\$@\"" >/usr/local/bin/--${verb} && chmod +x /usr/local/bin/--${verb} \
   ; done
diff --git a/acme.sh b/acme.sh
index 66291224..2786bbc5 100755
--- a/acme.sh
+++ b/acme.sh
@@ -1,6 +1,6 @@
 #!/usr/bin/env sh
 
-VER=3.0.1
+VER=3.0.2
 
 PROJECT_NAME="acme.sh"
 
@@ -59,6 +59,9 @@ VTYPE_HTTP="http-01"
 VTYPE_DNS="dns-01"
 VTYPE_ALPN="tls-alpn-01"
 
+ID_TYPE_DNS="dns"
+ID_TYPE_IP="ip"
+
 LOCAL_ANY_ADDRESS="0.0.0.0"
 
 DEFAULT_RENEW=60
@@ -426,13 +429,11 @@ _secure_debug3() {
 }
 
 _upper_case() {
-  # shellcheck disable=SC2018,SC2019
-  tr 'a-z' 'A-Z'
+  tr '[:lower:]' '[:upper:]'
 }
 
 _lower_case() {
-  # shellcheck disable=SC2018,SC2019
-  tr 'A-Z' 'a-z'
+  tr '[:upper:]' '[:lower:]'
 }
 
 _startswith() {
@@ -1222,19 +1223,27 @@ _createcsr() {
 
   if [ "$acmeValidationv1" ]; then
     domainlist="$(_idn "$domainlist")"
-    printf -- "\nsubjectAltName=DNS:$domainlist" >>"$csrconf"
+    _debug2 domainlist "$domainlist"
+    alt=""
+    for dl in $(echo "$domainlist" | tr "," ' '); do
+      if [ "$alt" ]; then
+        alt="$alt,$(_getIdType "$dl" | _upper_case):$dl"
+      else
+        alt="$(_getIdType "$dl" | _upper_case):$dl"
+      fi
+    done
+    printf -- "\nsubjectAltName=$alt" >>"$csrconf"
   elif [ -z "$domainlist" ] || [ "$domainlist" = "$NO_VALUE" ]; then
     #single domain
     _info "Single domain" "$domain"
-    printf -- "\nsubjectAltName=DNS:$(_idn "$domain")" >>"$csrconf"
+    printf -- "\nsubjectAltName=$(_getIdType "$domain" | _upper_case):$(_idn "$domain")" >>"$csrconf"
   else
     domainlist="$(_idn "$domainlist")"
     _debug2 domainlist "$domainlist"
-    if _contains "$domainlist" ","; then
-      alt="DNS:$(_idn "$domain"),DNS:$(echo "$domainlist" | sed "s/,,/,/g" | sed "s/,/,DNS:/g")"
-    else
-      alt="DNS:$(_idn "$domain"),DNS:$domainlist"
-    fi
+    alt="$(_getIdType "$domain" | _upper_case):$domain"
+    for dl in $(echo "$domainlist" | tr "," ' '); do
+      alt="$alt,$(_getIdType "$dl" | _upper_case):$dl"
+    done
     #multi
     _info "Multi domain" "$alt"
     printf -- "\nsubjectAltName=$alt" >>"$csrconf"
@@ -4174,6 +4183,36 @@ _match_issuer() {
   _contains "$_rootissuer" "$_missuer"
 }
 
+#ip
+_isIPv4() {
+  for seg in $(echo "$1" | tr '.' ' '); do
+    if [ $seg -ge 0 ] 2>/dev/null && [ $seg -le 255 ] 2>/dev/null; then
+      continue
+    fi
+    return 1
+  done
+  return 0
+}
+
+#ip6
+_isIPv6() {
+  _contains "$1" ":"
+}
+
+#ip
+_isIP() {
+  _isIPv4 "$1" || _isIPv6 "$1"
+}
+
+#identifier
+_getIdType() {
+  if _isIP "$1"; then
+    echo "$ID_TYPE_IP"
+  else
+    echo "$ID_TYPE_DNS"
+  fi
+}
+
 #webroot, domain domainlist  keylength
 issue() {
   if [ -z "$2" ]; then
@@ -4330,7 +4369,7 @@ issue() {
   dvsep=','
   if [ -z "$vlist" ]; then
     #make new order request
-    _identifiers="{\"type\":\"dns\",\"value\":\"$(_idn "$_main_domain")\"}"
+    _identifiers="{\"type\":\"$(_getIdType "$_main_domain")\",\"value\":\"$(_idn "$_main_domain")\"}"
     _w_index=1
     while true; do
       d="$(echo "$_alt_domains," | cut -d , -f "$_w_index")"
@@ -4339,7 +4378,7 @@ issue() {
       if [ -z "$d" ]; then
         break
       fi
-      _identifiers="$_identifiers,{\"type\":\"dns\",\"value\":\"$(_idn "$d")\"}"
+      _identifiers="$_identifiers,{\"type\":\"$(_getIdType "$d")\",\"value\":\"$(_idn "$d")\"}"
     done
     _debug2 _identifiers "$_identifiers"
     if ! _send_signed_request "$ACME_NEW_ORDER" "{\"identifiers\": [$_identifiers]}"; then
@@ -5674,8 +5713,16 @@ installcronjob() {
   if [ -f "$LE_WORKING_DIR/$PROJECT_ENTRY" ]; then
     lesh="\"$LE_WORKING_DIR\"/$PROJECT_ENTRY"
   else
-    _err "Can not install cronjob, $PROJECT_ENTRY not found."
-    return 1
+    _debug "_SCRIPT_" "$_SCRIPT_"
+    _script="$(_readlink "$_SCRIPT_")"
+    _debug _script "$_script"
+    if [ -f "$_script" ]; then
+      _info "Using the current script from: $_script"
+      lesh="$_script"
+    else
+      _err "Can not install cronjob, $PROJECT_ENTRY not found."
+      return 1
+    fi
   fi
   if [ "$_c_home" ]; then
     _c_entry="--config-home \"$_c_home\" "
@@ -5902,7 +5949,7 @@ _deactivate() {
     _initAPI
   fi
 
-  _identifiers="{\"type\":\"dns\",\"value\":\"$_d_domain\"}"
+  _identifiers="{\"type\":\"$(_getIdType "$_d_domain")\",\"value\":\"$_d_domain\"}"
   if ! _send_signed_request "$ACME_NEW_ORDER" "{\"identifiers\": [$_identifiers]}"; then
     _err "Can not get domain new order."
     return 1
@@ -5938,7 +5985,7 @@ _deactivate() {
       thumbprint="$(__calc_account_thumbprint)"
     fi
     _debug "Trigger validation."
-    vtype="$VTYPE_DNS"
+    vtype="$(_getIdType "$_d_domain")"
     entry="$(echo "$response" | _egrep_o '[^\{]*"type":"'$vtype'"[^\}]*')"
     _debug entry "$entry"
     if [ -z "$entry" ]; then
diff --git a/deploy/synology_dsm.sh b/deploy/synology_dsm.sh
index 5a70c74e..177b3fbe 100644
--- a/deploy/synology_dsm.sh
+++ b/deploy/synology_dsm.sh
@@ -100,6 +100,7 @@ synology_dsm_deploy() {
   if [ -z "$token" ]; then
     _err "Unable to authenticate to $SYNO_Hostname:$SYNO_Port using $SYNO_Scheme."
     _err "Check your username and password."
+    _err "If two-factor authentication is enabled for the user, you have to choose another user."
     return 1
   fi
   sid=$(echo "$response" | grep "sid" | sed -n 's/.*"sid" *: *"\([^"]*\).*/\1/p')
diff --git a/notify/feishu.sh b/notify/feishu.sh
new file mode 100644
index 00000000..18693c2d
--- /dev/null
+++ b/notify/feishu.sh
@@ -0,0 +1,48 @@
+#!/usr/bin/env sh
+
+#Support feishu webhooks api
+
+#required
+#FEISHU_WEBHOOK="xxxx"
+
+#optional
+#FEISHU_KEYWORD="yyyy"
+
+# subject content statusCode
+feishu_send() {
+  _subject="$1"
+  _content="$2"
+  _statusCode="$3" #0: success, 1: error 2($RENEW_SKIP): skipped
+  _debug "_subject" "$_subject"
+  _debug "_content" "$_content"
+  _debug "_statusCode" "$_statusCode"
+
+  FEISHU_WEBHOOK="${FEISHU_WEBHOOK:-$(_readaccountconf_mutable FEISHU_WEBHOOK)}"
+  if [ -z "$FEISHU_WEBHOOK" ]; then
+    FEISHU_WEBHOOK=""
+    _err "You didn't specify a feishu webhooks FEISHU_WEBHOOK yet."
+    _err "You can get yours from https://www.feishu.cn"
+    return 1
+  fi
+  _saveaccountconf_mutable FEISHU_WEBHOOK "$FEISHU_WEBHOOK"
+
+  FEISHU_KEYWORD="${FEISHU_KEYWORD:-$(_readaccountconf_mutable FEISHU_KEYWORD)}"
+  if [ "$FEISHU_KEYWORD" ]; then
+    _saveaccountconf_mutable FEISHU_KEYWORD "$FEISHU_KEYWORD"
+  fi
+
+  _content=$(echo "$_content" | _json_encode)
+  _subject=$(echo "$_subject" | _json_encode)
+  _data="{\"msg_type\": \"text\", \"content\": {\"text\": \"[$FEISHU_KEYWORD]\n$_subject\n$_content\"}}"
+
+  response="$(_post "$_data" "$FEISHU_WEBHOOK" "" "POST" "application/json")"
+
+  if [ "$?" = "0" ] && _contains "$response" "StatusCode\":0"; then
+    _info "feishu webhooks event fired success."
+    return 0
+  fi
+
+  _err "feishu webhooks event fired error."
+  _err "$response"
+  return 1
+}
diff --git a/notify/mail.sh b/notify/mail.sh
index 2cbddb63..656dd371 100644
--- a/notify/mail.sh
+++ b/notify/mail.sh
@@ -62,7 +62,7 @@ mail_send() {
   fi
 
   contenttype="text/plain; charset=utf-8"
-  subject="=?UTF-8?B?$(echo "$_subject" | _base64)?="
+  subject="=?UTF-8?B?$(printf -- "%b" "$_subject" | _base64)?="
   result=$({ _mail_body | eval "$(_mail_cmnd)"; } 2>&1)
 
   # shellcheck disable=SC2181
@@ -131,6 +131,7 @@ _mail_body() {
     echo "To: $MAIL_TO"
     echo "Subject: $subject"
     echo "Content-Type: $contenttype"
+    echo "MIME-Version: 1.0"
     echo
     ;;
   esac