New Select Edges by Convexity
Select all Convex or Concave edges which faces angle is over the given Angle Threshold.
Ctrl+Click: on Convex or Concave buttons enables the interactive mode, which is optimized for large meshes and allows you to instantly select the edges while changing the Angle Threshold.
The Get button gets the angle between the selected edge faces.
Select Hard Edges
Select all the edges which faces do not shared any Smoothing Group.
Expand Selection By Smoothing Group
Expands the current selected faces using their exact Smoothing Group.
Expand Selection By Smoothing Surface
Expands the current selected faces using any of their Smoothing Groups.
Expand Selection By Element
Expands the current selected faces to the mesh Element.
In Face mode Isolates the current selected faces.
In Edge mode Isolates the faces using the selected edges..
In Vertex mode Isolates the faces using the selected vertices.
Shift+Click: Automatically isolate the Element using the selected faces.
Ctrl+Click: Zoom the selected faces.