Improve documentation

Author: mwaskom

doc/_docstrings/objects.Plot.layout.ipynb

@@ -69,10 +69,28 @@
     "p.facet([\"A\", \"B\"], [\"X\", \"Y\"]).layout(engine=\"constrained\")"
    ]
   },
+  {
+   "cell_type": "markdown",
+   "id": "d61054d1-dcef-4e11-9802-394bcc633f9f",
+   "metadata": {},
+   "source": [
+    "With `extent`, you can control the size of the plot relative to the underlying figure. Because the notebook display adapts the figure background to the plot, this appears only to change the plot size in a notebook context. But it can be useful when saving or displaying through a `pyplot` GUI window:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "1b5d5969-2925-474f-8e3c-99e4f90a7a2b",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "p.layout(extent=[0, 0, .8, 1]).show()"
+   ]
+  },
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "781ff58c-b805-4e93-8cae-be0442e273ea",
+   "id": "e5c41b7d-a064-4406-8571-a544b194f3dc",
    "metadata": {},
    "outputs": [],
    "source": []

seaborn/_core/plot.py

@@ -831,13 +831,14 @@ def layout(
         size : (width, height)
             Size of the resulting figure, in inches. Size is inclusive of legend when
             using pyplot, but not otherwise.
-        engine : {{"tight", "constrained", None}}
+        engine : {{"tight", "constrained", "none"}}
             Name of method for automatically adjusting the layout to remove overlap.
             The default depends on whether :meth:`Plot.on` is used.
         extent : (left, bottom, right, top)
-            Boundaries of the plot layout, in fractions of the figure size.
-            Note: the extent includes of axis decorations when using a layout engine,
-            but it is exclusive when `engine=None`.
+            Boundaries of the plot layout, in fractions of the figure size. Takes
+            effect through the layout engine; exact results will vary across engines.
+            Note: the extent includes axis decorations when using a layout engine,
+            but it is exclusive of them when `engine="none"`.
 
         Examples
         --------