Related to https://gitlab.com/groups/gitlab-org/-/epics/2697   Example use cases: * When GitLab is used for Service Desk scenarios and Support team members want to discuss details in the context of an issue but don't want to overload the issue reporter with details. * For companies with a public issue tracker, this feature enables team members the ability to discuss and share internal data related to feature development. GitLab is a great example! ## Why? The majority of the work for this feature has been completed but is behind a feature flag. Getting this across the finish line aligns with our engineering OKR to reduce WIP. ## MVC Proposal - Limit scope to discussion notes on Issues and Epics. - Limit the note types that supports confidentiality to comments and replies (exclude diff, image diff and any other notes) - Only allow confidentiality of parent notes in discussions. If private, all replies are private by default. - No togglability of parent note or replies. - Support making the note confidential on creation via API. - Make sure the scope is secure and information is not leaked. Exclude unauthorised users from notifications altogether if necessary. <!-- triage-serverless v3 PLEASE DO NOT REMOVE THIS SECTION --> *This page may contain information related to upcoming products, features and functionality. It is important to note that the information presented is for informational purposes only, so please do not rely on the information for purchasing or planning purposes. Just like with all projects, the items mentioned on the page are subject to change or delay, and the development, release, and timing of any products, features, or functionality remain at the sole discretion of GitLab Inc.* <!-- triage-serverless v3 PLEASE DO NOT REMOVE THIS SECTION -->