Linking puts work in order, so one task or tag starts when another finishes. On a board, linked tags form a chain. In the Gantt view, linked tasks are shown with arrows between their bars.
Chain tags on a board
Hold Ctrl (Cmd on a Mac) and click each tag you want to chain, in the order they should happen.
Click Chain Tags in the board toolbar.
Name the chain, or add the tags to an existing chain, and click Save. You'll see Chain created successfully.
The tags are linked in the order you selected them. Each one shows a chain icon, and flowlines connect them on the board.
See or remove links on a tag
Click the chain icon on a tag to see every tag it's linked to. To remove one, click the Un-Link icon next to it in the list.
Chain Manager
Chain Manager lists every chain on the board in a widget. Click the eye icon next to a chain's name to show only that chain's tags, which makes long chains easier to follow.
Link tasks in the Gantt view
Hold Shift and select the tasks, in order.
Click Link tasks in the toolbar, or press Ctrl+L. Each task is linked finish-to-start to the one before it.
To remove links, select the tasks and click Unlink tasks (Ctrl+U).
To change the link type (for example, start-to-start) or add lag, open the task (F2) and use the Predecessors tab. See How to Change Dependencies on Predecessors.
Ask Brena
Brena can link tasks for you, for example: "Link these subtasks finish-to-start in order." See Editing Tasks in Bulk with Brena.