Document WorldBoundaryShape3D having a finite size when using Jolt Physics

This also mentions Jolt Physics in the ProjectSettings 3D physics engine
documentation.

doc/classes/ProjectSettings.xml

@@ -2237,8 +2237,10 @@
 		</member>
 		<member name="physics/2d/physics_engine" type="String" setter="" getter="" default="&quot;DEFAULT&quot;">
 			Sets which physics engine to use for 2D physics.
-			"DEFAULT" and "GodotPhysics2D" are the same, as there is currently no alternative 2D physics server implemented.
-			"Dummy" is a 2D physics server that does nothing and returns only dummy values, effectively disabling all 2D physics functionality.
+			[b]DEFAULT[/b] is currently equivalent to [b]GodotPhysics2D[/b], but may change in future releases. Select an explicit implementation if you want to ensure that your project stays on the same engine.
+			[b]GodotPhysics2D[/b] is Godot's internal 2D physics engine.
+			[b]Dummy[/b] is a 2D physics server that does nothing and returns only dummy values, effectively disabling all 2D physics functionality.
+			Third-party extensions and modules can add other physics engines to select with this setting.
 		</member>
 		<member name="physics/2d/run_on_separate_thread" type="bool" setter="" getter="" default="false">
 			If [code]true[/code], the 2D physics server runs on a separate thread, making better use of multi-core CPUs. If [code]false[/code], the 2D physics server runs on the main thread. Running the physics server on a separate thread can increase performance, but restricts API access to only physics process.
@@ -2316,8 +2318,11 @@
 		</member>
 		<member name="physics/3d/physics_engine" type="String" setter="" getter="" default="&quot;DEFAULT&quot;">
 			Sets which physics engine to use for 3D physics.
-			"DEFAULT" and "GodotPhysics3D" are the same, as there is currently no alternative 3D physics server implemented.
-			"Dummy" is a 3D physics server that does nothing and returns only dummy values, effectively disabling all 3D physics functionality.
+			[b]DEFAULT[/b] is currently equivalent to [b]GodotPhysics3D[/b], but may change in future releases. Select an explicit implementation if you want to ensure that your project stays on the same engine.
+			[b]GodotPhysics3D[/b] is Godot's internal 3D physics engine.
+			[b]Jolt Physics[/b] is an alternative physics engine that is generally faster and more reliable than [b]GodotPhysics3D[/b]. As it was recently implemented, it is currently considered experimental and its behavior may change in future releases.
+			[b]Dummy[/b] is a 3D physics server that does nothing and returns only dummy values, effectively disabling all 3D physics functionality.
+			Third-party extensions and modules can add other physics engines to select with this setting.
 		</member>
 		<member name="physics/3d/run_on_separate_thread" type="bool" setter="" getter="" default="false">
 			If [code]true[/code], the 3D physics server runs on a separate thread, making better use of multi-core CPUs. If [code]false[/code], the 3D physics server runs on the main thread. Running the physics server on a separate thread can increase performance, but restricts API access to only physics process.

doc/classes/WorldBoundaryShape3D.xml

@@ -5,6 +5,7 @@
 	</brief_description>
 	<description>
 		A 3D world boundary shape, intended for use in physics. [WorldBoundaryShape3D] works like an infinite plane that forces all physics bodies to stay above it. The [member plane]'s normal determines which direction is considered as "above" and in the editor, the line over the plane represents this direction. It can for example be used for endless flat floors.
+		[b]Note:[/b] When the physics engine is set to [b]Jolt Physics[/b] in the project settings ([member ProjectSettings.physics/3d/physics_engine]), [WorldBoundaryShape3D] has a finite size (centered at the world origin). It can be adjusted by changing [member ProjectSettings.physics/jolt_physics_3d/limits/world_boundary_shape_size].
 	</description>
 	<tutorials>
 	</tutorials>