diff --git a/changelog/7366.feature.md b/changelog/7366.feature.md
new file mode 100644
index 000000000000..70be845e4041
--- /dev/null
+++ b/changelog/7366.feature.md
@@ -0,0 +1,2 @@
+Allow to reaction of rasa chatbot to slack opening / switching window of conversation. This allows the chatbot to provide 
+a "welcome message" to the user.
\ No newline at end of file
diff --git a/docs/docs/connectors/slack.mdx b/docs/docs/connectors/slack.mdx
index 2766e16f7a89..c85b5491c874 100644
--- a/docs/docs/connectors/slack.mdx
+++ b/docs/docs/connectors/slack.mdx
@@ -136,6 +136,13 @@ your bot and tell you about new messages. If you are running locally, you can
    sending of messages, you'll be prompted to **reinstall your app** which you will
    need to do. Otherwise, Slack will confirm your change with a **Success!**)
 
+## Optional: Initial message
+   If you want to have the bot greet message appear every time when user opens its chat (e.g. for the first time) you want
+   to send some subscribe to `app_home_opened` event. This will automatically redirect to expected `init` intent in your 
+   domain (it might be smart to handle if a user has already encountered a chatbot and not react to this event every single
+   time).
+
+
 Your bot is now ready to go and will receive webhook notifications about new messages.
 ## Optional: Interactive Components
 After you've completed [Sending Messages](./slack.mdx#sending-messages) and
diff --git a/rasa/core/channels/slack.py b/rasa/core/channels/slack.py
index 65bff1ae893e..031e8f277715 100644
--- a/rasa/core/channels/slack.py
+++ b/rasa/core/channels/slack.py
@@ -235,6 +235,28 @@ def _is_user_message(slack_event: Dict[Text, Any]) -> bool:
             )
             and slack_event.get("event", {}).get("text")
             and not slack_event.get("event", {}).get("bot_id")
+        ) or SlackInput._is_init_message(slack_event)
+
+    @staticmethod
+    def _is_init_message(slack_event: Dict[Text, Any]) -> bool:
+        """
+        This method determines if a message sent is an initial message
+        from Slack when the user opens up the window with chatbot conversation.
+
+        This can happen multiple times throughout the conversation and the user 
+        needs to handle this on the chatbot side only actually invoking 
+        init intent e.g. if a certain time (like 24 hours) have passed since
+        last time welcome message (=init intent) display.
+
+        By default the init intent is not invoked as this message is normally
+        not invoked by Slack. For this method to work it needs to be subscribed
+        to in event subscription. 
+        Args:
+            slack_event: event from slack saying that user has started chatbot interaction
+        """
+        return (
+            slack_event.get("event") is not None
+            and slack_event.get("event", {}).get("type") == "app_home_opened"
         )
 
     @staticmethod
@@ -297,6 +319,7 @@ def _is_interactive_message(payload: Dict) -> bool:
             "channels_select",
             "overflow",
             "datepicker",
+            "multi_static_select",
         ]
         if payload.get("actions"):
             action_type = payload["actions"][0].get("type")
@@ -309,6 +332,13 @@ def _is_interactive_message(payload: Dict) -> bool:
                 )
         return False
 
+    @staticmethod
+    def _get_text_from_multi_select(action: Dict) -> Optional[Text]:
+        values = []
+        for val in action.get("selected_options"):
+            values.append(val.get("value"))
+        return ",".join(values)
+
     @staticmethod
     def _get_interactive_response(action: Dict) -> Optional[Text]:
         """Parse the payload for the response value."""
@@ -331,6 +361,8 @@ def _get_interactive_response(action: Dict) -> Optional[Text]:
             return action.get("selected_option", {}).get("value")
         elif action["type"] == "datepicker":
             return action.get("selected_date")
+        elif action["type"] == "multi_static_select":
+            return SlackInput._get_text_from_multi_select(action)
 
     async def process_message(
         self,
@@ -519,7 +551,9 @@ async def webhook(request: Request) -> HTTPResponse:
                         "a user message. Skipping message."
                     )
                     return response.text("Bot message delivered.")
-
+                if self._is_init_message(output):
+                    logger.debug("Init message recieved - sending to /init intent")
+                    user_message = "/init"
                 if not self._is_supported_channel(output, metadata):
                     logger.warning(
                         f"Received message on unsupported channel: {metadata['out_channel']}"
@@ -564,6 +598,7 @@ def _is_supported_channel(self, slack_event: Dict, metadata: Dict) -> bool:
             self._is_direct_message(slack_event)
             or self._is_app_mention(slack_event)
             or metadata["out_channel"] == self.slack_channel
+            or self._is_init_message(slack_event)
         )
 
     def get_output_channel(
diff --git a/tests/core/channels/test_slack.py b/tests/core/channels/test_slack.py
index f24d1ddb5429..20a3d82d9626 100644
--- a/tests/core/channels/test_slack.py
+++ b/tests/core/channels/test_slack.py
@@ -356,6 +356,20 @@ def test_is_slack_message_false():
     assert SlackInput._is_user_message(slack_message) is False
 
 
+def test_is_slack_message_true_init():
+
+    event = {
+        "type": "app_home_opened",
+        "user": "UFDM2MG77",
+        "channel": "A01G7854KUU",
+        "tab": "messages",
+        "event_ts": "1606315650.276505",
+    }
+    payload = json.dumps({"event": event})
+    slack_message = json.loads(payload)
+    assert SlackInput._is_user_message(slack_message) is True
+
+
 def test_slackbot_init_one_parameter():
     from rasa.core.channels.slack import SlackBot