When you right-click a Gantt chart, a context menu appears.
Items in the menu depend on where you right-click.

You can filter tasks with context menus.

Grid header context menu

It’s the context menu when you right-click on the grid header.
The items are related to the visibility of columns.

Timeline header context menu

It’s the context menu when you right-click on the timeline header.
The items are related to the timeline panel.

Task context menu

The task context menu is only enabled in edit mode.

It’s the context menu when you right-click on a task row.
The items are related to task operations.