Jira 8.3.x and 8.4.x Compatibility & bug fixes before 2.0 release.
- fixed an issue where the Jira activity stream would show tasks from Issues the current user doesn't have access to
- fixed several issues with filtering in Project Tasks and My Tasks
- fixed an issue where mentioning multiple users in a Task resulted in bad output in Project Tasks
- fixed custom fields to not install multiple times during upgrades
- fixed an issue when a task mentions a deleted user
- added a new workflow validator, to validate if open tasks are present