The Slack App Alert Integration TA is meant to integrate with Slack Apps, the new way of communicating with Slack in favor of the deprecated Incoming Webhooks integration. The Incoming Webhooks integration allows sending messages to multiple channels which is highly flexible. A Slack App has to join a channel before it can post messages in it, but using the correct configuration in combination with this TA, a Slack App can join a channel if needed and post messages to it with customized bot name and emoji icon.