Create a new scenario in Make (formerly Integromat) and choose the Facebook Groups app from the list of available apps.
Select the Get new updates from group trigger.
Enter the Group ID of the Facebook Group you want to monitor for new updates and click the Continue button.
Add the Slack app to your scenario.
Select the Send a message in channel action.
Enter the channel name or ID in the Channel field.
Enter the message text in the Message field.
Click the Continue button.
Set up the scenario and click the Run button.
You can use this scenario to automatically send messages in Slack whenever a new update is posted to a selected Facebook Group. This can be useful for keeping members of your team up-to-date on what's happening in the group.