Rail joins are determined according to the type properties of the continuous rail, or you can override an individual join method and select miter or fillet. For information on overriding joins for the railing system, see Modifying Railing Joins.
A box displays around the join as you move your cursor over it.
The default join method is specified in the type properties for the continuous rail. If you select By type as the join method, the default is applied. See Continuous Rail Type Properties.