What does it mean to block a task?

Blocking a task means marking it as temporarily unworkable due to an issue preventing progress. The Card Blocking feature helps visualize this by “freezing” the card until the problem is resolved.

Kanban Tool Card Blocking Feature

Blocked tasks can’t be moved using the standard drag-and-drop action, making it clear that work is on hold. To use this feature, just enable the Card Blocking power-up.