### Background We still have the MR sidebar updates behind a feature flag but we'd like to enable it globally. In order to do so, we should probably ensure that there's a little bit more consistency between issues, epics, (other issuables?), and merge requests. ### Proposal - Move several sidebar items into the dropdown at the top to maintain relative parity with MR - lock, copy reference, copy email, notifications - Add popover to alert users to the moved items - Popover should appear on both issues and MRs - Once dismissed from either location, it shouldn't show again - Popover copy: `Notifications, <issue/merge request/etc> lock, and other actions are available in this dropdown list.` - Add behind same `:moved_mr_sidebar` feature flag ##### Issue - Notifications - Lock issue - Copy reference - Copy email email ##### Epic - Notifications - Copy reference ##### Incident - Notifications - Copy reference - Copy email | Current | Proposal | Popover | | ------ | ------ | ------ | |  |  |  |