diff --git a/sat/plugins/plugin_xep_0428.py b/sat/plugins/plugin_xep_0428.py
new file mode 100644
index 00000000..88e1742b
--- /dev/null
+++ b/sat/plugins/plugin_xep_0428.py
@@ -0,0 +1,87 @@
+#!/usr/bin/env python3
+
+# Copyright (C) 2009-2022 Jérôme Poisson (goffi@goffi.org)
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+from typing import Optional
+
+from twisted.words.protocols.jabber import xmlstream
+from twisted.words.xish import domish
+from wokkel import disco
+from zope.interface import implementer
+
+from sat.core.constants import Const as C
+from sat.core.i18n import _
+from sat.core.log import getLogger
+
+log = getLogger(__name__)
+
+
+PLUGIN_INFO = {
+    C.PI_NAME: "Fallback Indication",
+    C.PI_IMPORT_NAME: "XEP-0428",
+    C.PI_TYPE: "XEP",
+    C.PI_PROTOCOLS: ["XEP-0428"],
+    C.PI_MAIN: "XEP_0428",
+    C.PI_HANDLER: "yes",
+    C.PI_DESCRIPTION: _("""Implementation of XEP-0428 (Fallback Indication)"""),
+}
+
+NS_FALLBACK = "urn:xmpp:fallback:0"
+
+
+class XEP_0428(object):
+
+    def __init__(self, host):
+        log.info(_("XEP-0428 (Fallback Indication) plugin initialization"))
+        host.registerNamespace("fallback", NS_FALLBACK)
+
+    def addFallbackElt(
+        self,
+        message_elt: domish.Element,
+        msg: Optional[str] = None
+    ) -> None:
+        """Add the fallback indication element
+
+        @param message_elt: <message> element where the indication must be
+            set
+        @param msg: message to show as fallback
+            Will be added as <body>
+        """
+        message_elt.addElement((NS_FALLBACK, "fallback"))
+        if msg is not None:
+            message_elt.addElement("body", content=msg)
+
+    def hasFallback(self, message_elt: domish.Element) -> bool:
+        """Tell if a message has a fallback indication"""
+        try:
+            next(message_elt.elements(NS_FALLBACK, "fallback"))
+        except StopIteration:
+            return False
+        else:
+            return True
+
+    def getHandler(self, __):
+        return XEP_0428_handler()
+
+
+@implementer(disco.IDisco)
+class XEP_0428_handler(xmlstream.XMPPHandler):
+
+    def getDiscoInfo(self, __, target, nodeIdentifier=""):
+        return [disco.DiscoFeature(NS_FALLBACK)]
+
+    def getDiscoItems(self, requestor, target, nodeIdentifier=""):
+        return []