### Problem to solve Current implementation of Epics has a participants widget in the right sidebar. The widget shows all participants who have interacted with the epic, including comments, replies or even emoji actions. {width=279 height=141} ### Proposal Add support for participants in work items in order to allow support for them in epics and issues as well. Ideally, this widget should be available for all kinds of work items. This is not dependent on any other changes to the work item detail view. ### UX See https://gitlab.com/gitlab-org/gitlab/-/issues/432154