The Border is the area of precisely definable width between the outside edge of a mat and the edge of the opening(s).
Apply Borders
Borders: Apply Borders To Top/Bottom Layer: Properties Tab
Borders and the Dynamic Outsides
Borders: Even Borders: Properties Tab
Borders: Lock Borders: Properties Tab
Borders: Preview Tab
Borders Properties
Borders: Single Tab
Border Size Fields: Properties Tab
Borders Toggle: Editor Tools
Change Borders: Design Edit Menu
Design Editor Keyboard Shortcuts
Dynamic Outsides
Dynamic Outsides Toggle: Editor Tools
Dynamic Outsides Toggle: Trace
Dynamic Outsides: Visualize Tools
Editing the Individual Border Sizes: Preview Tab
Grow the Borders: Preview Tab
Positioning Toggle: Editor Tools
Shrink the Borders: Preview Tab
Single Tab Borders: Separate Left and Right Borders
Using the Borders
Apply Borders To: Editor Default Setting
Borders: Editor Default Setting
Border Sizes: Editor Default Setting
Borders Order: Application Default Setting
Borders Toggle: Editor Default Setting
Dynamic Outsides Toggle: Editor Default Setting
Even Borders: Editor Default Setting
Layer Direction: Application Default Setting
Lock Borders: Editor Default Setting