Layout: Chart Items, Data source update (#10860)

Author: selmaVH1

docs/user_manual/print_layout/layout_items/img/chart_datasource.png

@@ -146,6 +146,11 @@ In this section, select and configure the layer and fields you want to display i
 #. Double-click a series name to rename it.
 #. Click :guilabel:`Modify Series...` button and define the :guilabel:`X-axis` and :guilabel:`Y-axis` fields using the drop-down lists.
    Optionally, add a filter expression to display only specific data in the chart.
+#. Check the |checkbox| :guilabel:`Use only features visible within a map` option to include only features that are currently visible
+   in a layout map item. From the :guilabel:`Linked map` drop-down list, select the map to link the chart to.
+#. Check the |checkbox| :guilabel:`Use only features intersecting atlas features` option to include only features that intersect
+   with the :ref:`atlas feature <atlas_generation>`.
+
 
 .. figure:: img/chart_datasource.png
    :align: center