Borders(margins) of UV islands. — Right-Click Select
Set camera and render resolution to border in 1 click — Right-Click Select
Border Occlude - Released Scripts and Themes - Blender Artists Community
Set plain border or edge to object in render blender engine - YouTube
View Regions — Blender Manual
How to make an animated border introduction Blender [2.9] - YouTube
A procedural material that creates a border around a plane and matches the size ratio of the object - Materials and Textures - Blender Artists Community
Blender Subdivision UV border problem - Blender Stack Exchange