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diff --git a/docs/src/templates/assets/javascripts/browser/viewport/offset/index.ts b/docs/src/templates/assets/javascripts/browser/viewport/offset/index.ts
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+/*
+ * Copyright (c) 2016-2023 Martin Donath <martin.donath@squidfunk.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+import {
+  Observable,
+  fromEvent,
+  map,
+  merge,
+  startWith
+} from "rxjs"
+
+/* ----------------------------------------------------------------------------
+ * Types
+ * ------------------------------------------------------------------------- */
+
+/**
+ * Viewport offset
+ */
+export interface ViewportOffset {
+  x: number                            /* Horizontal offset */
+  y: number                            /* Vertical offset */
+}
+
+/* ----------------------------------------------------------------------------
+ * Functions
+ * ------------------------------------------------------------------------- */
+
+/**
+ * Retrieve viewport offset
+ *
+ * On iOS Safari, viewport offset can be negative due to overflow scrolling.
+ * As this may induce strange behaviors downstream, we'll just limit it to 0.
+ *
+ * @returns Viewport offset
+ */
+export function getViewportOffset(): ViewportOffset {
+  return {
+    x: Math.max(0, scrollX),
+    y: Math.max(0, scrollY)
+  }
+}
+
+/* ------------------------------------------------------------------------- */
+
+/**
+ * Watch viewport offset
+ *
+ * @returns Viewport offset observable
+ */
+export function watchViewportOffset(): Observable<ViewportOffset> {
+  return merge(
+    fromEvent(window, "scroll", { passive: true }),
+    fromEvent(window, "resize", { passive: true })
+  )
+    .pipe(
+      map(getViewportOffset),
+      startWith(getViewportOffset())
+    )
+}