1) You can't assign an issue to multiple users. But you could add a custom field which contains multiple users.Then your users can search in JQL if their user is inside this field. (currentUser() in MyMultipleAssigneesField). https://confluence.atlassian.com/display/JIRA/Adding+a+Custom+Field
2) You can do this with Bulk Edit: https://confluence.atlassian.com/display/JIRA/Modifying+Multiple+%28%27Bulk%27%29+Issues
...ollected feedback from users around the lack of shortcuts, and we’re here to address that: In next-gen projects, I miss the keyboard shortcuts badly. This is particularly true on the Board, but also i...
Connect with like-minded Atlassian users at free events near you!Find an event
Connect with like-minded Atlassian users at free events near you!
Unfortunately there are no Community Events near you at the moment.Host an event
You're one step closer to meeting fellow Atlassian users at your local event. Learn more about Community Events