tweak

Author: Rich-Harris

packages/svelte/src/reactivity/window/index.js

@@ -53,7 +53,7 @@ export const outerHeight = new ReactiveValue(
 );
 
 /**
- * `screenLeft.current` is a reactive view of `window.screenLeft`. On the server it is `undefined`.
+ * `screenLeft.current` is a reactive view of `window.screenLeft`. It is updated inside a `requestAnimationFrame` callback. On the server it is `undefined`.
  */
 export const screenLeft = new ReactiveValue(
 	BROWSER ? () => window.screenLeft : () => undefined,
@@ -75,7 +75,7 @@ export const screenLeft = new ReactiveValue(
 );
 
 /**
- * `screenTop.current` is a reactive view of `window.screenTop`. On the server it is `undefined`.
+ * `screenTop.current` is a reactive view of `window.screenTop`. It is updated inside a `requestAnimationFrame` callback. On the server it is `undefined`.
  */
 export const screenTop = new ReactiveValue(
 	BROWSER ? () => window.screenTop : () => undefined,

packages/svelte/types/index.d.ts

@@ -1988,11 +1988,11 @@ declare module 'svelte/reactivity/window' {
 	 */
 	export const outerHeight: ReactiveValue<number | undefined>;
 	/**
-	 * `screenLeft.current` is a reactive view of `window.screenLeft`. On the server it is `undefined`.
+	 * `screenLeft.current` is a reactive view of `window.screenLeft`. It is updated inside a `requestAnimationFrame` callback. On the server it is `undefined`.
 	 */
 	export const screenLeft: ReactiveValue<number | undefined>;
 	/**
-	 * `screenTop.current` is a reactive view of `window.screenTop`. On the server it is `undefined`.
+	 * `screenTop.current` is a reactive view of `window.screenTop`. It is updated inside a `requestAnimationFrame` callback. On the server it is `undefined`.
 	 */
 	export const screenTop: ReactiveValue<number | undefined>;
 	/**