diff --git a/README.md b/README.md
index 2174a73d..36149339 100644
--- a/README.md
+++ b/README.md
@@ -185,7 +185,9 @@ These are the default shortcuts. See `man 5 foot` and the example
 : Paste from _primary_ selection
 
 <kbd>right</kbd>
-: Extend current selection
+: Extend current selection. Clicking immediately extends the
+  selection, while hold-and-drag allows you to interactively resize
+  the selection.
 
 <kbd>wheel</kbd>
 : Scroll up/down in history
diff --git a/doc/foot.1.scd b/doc/foot.1.scd
index b8e5593a..c8b1f6e7 100644
--- a/doc/foot.1.scd
+++ b/doc/foot.1.scd
@@ -199,7 +199,9 @@ Note that these are just the defaults; they can be changed in the
 	Paste from the _primary_ selection
 
 *right*
-	Extend current selection
+	Extend current selection. Clicking immediately extends the
+	selection, while hold-and-drag allows you to interactively resize
+	the selection.
 
 *wheel*
 	Scroll up/down in history