I'm sorry, but the knowledge sources do not contain information about configuring the Slack webhook URL directly via environment variables in the Airbyte Helm chart. All available documentation describes setting up Slack notifications through the Airbyte UI, where you paste the webhook URL into the Notifications settings page and toggle notification types as needed. There is no mention of Helm chart values or environment variables for this configuration in the provided sources. If you need to automate this process, you may want to follow updates on related feature requests, such as allowing notification settings to be configured via the Airbyte API, which is currently an open issue and not yet available in the product [Allow for configuration of notification settings through Airbyte API](
https://github.com/airbytehq/airbyte/issues/44889). For now, you will need to configure Slack notifications manually through the Airbyte UI as described in the documentation: - Create a Slack app and obtain the webhook URL. - Go to
Settings > Notifications in Airbyte. - Paste the webhook URL and enable the desired notification types. - Save your changes and test the integration. If you require further automation, you may need to monitor the Airbyte GitHub issues and discussions for future enhancements in this area.