Toggling completion state of all items

Checking and unchecking all items at once may come in handy, e.g., when you want to resolve Jira issue while block issue transition feature is enabled.

Select "Complete/Uncomplete all items" option from the dropdown menu:

After using this option all items would be completed without the need for manual update of each of them:

The same option could be used once again to uncheck all items: