add mouse_follows_focus

crates/toml-spec/spec/spec.yaml

@@ -2903,7 +2903,7 @@ Config:
         focus to that window.
 
         The default is `true`.
-    unstable-mouse-follows-focus:
+    mouse-follows-focus:
       kind: boolean
       required: false
       description: |
@@ -2914,10 +2914,20 @@ Config:
         active window when focus changes through keyboard commands such as `focus-left`,
         `focus-right`, `show-workspace`, etc.
 
-        The default is `false`.
-        
-        This option is unstable due to various issues. It is not subject to the usual
-        semver guarantees.
+        The default is `true`.
+
+        - Example:
+
+          ```toml
+          mouse-follows-focus = false
+          ```
+    unstable-mouse-follows-focus:
+      kind: boolean
+      required: false
+      description: |
+        Legacy alias for `mouse-follows-focus`.
+
+        Prefer `mouse-follows-focus` in new configurations.
 
         - Example: