You don’t have to follow the classic scrum framework to be agile.
YouTrack team deviates from the classic scrum:
We don’t estimate tasks.
We continuously add new issues to the board during the sprint.
We split issues that were created during the planning into smaller tasks.
Only one issue can be in progress per person.
If one task is in progress for more than 3 days, a special workflow tags it and the team discuss the task.