Remove the scrollIntoView function

and rely on the HTMLElement.scrollIntoView function instead.

Author: calixteman

web/pdf_viewer.css

@@ -30,8 +30,8 @@
 
   --viewer-container-height: 0;
   --pdfViewer-padding-bottom: 0;
-  --page-margin: 1px auto -8px;
-  --page-border: 9px solid transparent;
+  --page-margin-top: 10px;
+  --page-outline: none;
   --spreadHorizontalWrapped-margin-LR: -3.5px;
   --loading-icon-delay: 400ms;
   --focus-ring-color: light-dark(#0060df, #0df);
@@ -42,8 +42,7 @@
 
   @media screen and (forced-colors: active) {
     --pdfViewer-padding-bottom: 9px;
-    --page-margin: 8px auto -1px;
-    --page-border: 1px solid CanvasText;
+    --page-outline: 1px solid CanvasText;
     --spreadHorizontalWrapped-margin-LR: 3.5px;
     --focus-ring-color: CanvasText;
     --new-badge-bg: AccentColor;
@@ -142,12 +141,18 @@
   direction: ltr;
   width: 816px;
   height: 1056px;
-  margin: var(--page-margin);
+  margin-inline: auto;
+  margin-block: var(--page-margin-top) 0;
   position: relative;
   overflow: visible;
-  border: var(--page-border);
+  outline: var(--page-outline);
   background-clip: content-box;
   background-color: var(--page-bg-color, rgb(255 255 255));
+  scroll-margin-top: calc(0 - var(--page-margin-top));
+
+  &:last-child {
+    margin-block-end: var(--page-margin-top);
+  }
 }
 
 .pdfViewer .dummyPage {

web/pdf_viewer.js

@@ -57,7 +57,6 @@ import {
   PresentationModeState,
   removeNullCharacters,
   SCROLLBAR_PADDING,
-  scrollIntoView,
   ScrollMode,
   SpreadMode,
   TextLayerMode,
@@ -1458,7 +1457,18 @@ class PDFViewer {
         pageSpot = { left: 0, top: 0 };
       }
     }
-    scrollIntoView(div, pageSpot);
+
+    div.scrollIntoView({
+      behavior: "auto",
+      block: "start",
+      inline: pageSpot ? "start" : "nearest",
+    });
+    if (pageSpot?.top) {
+      this.container.scrollTop += pageSpot.top;
+    }
+    if (pageSpot?.left) {
+      this.container.scrollLeft += pageSpot.left;
+    }
 
     // Ensure that the correct *initial* document position is set, when any
     // OpenParameters are used, for documents with non-default Scroll/Spread

web/ui_utils.js

@@ -69,49 +69,6 @@ const CursorTool = {
 // Used by `PDFViewerApplication`, and by the API unit-tests.
 const AutoPrintRegExp = /\bprint\s*\(/;
 
-/**
- * Scrolls specified element into view of its parent.
- * @param {HTMLElement} element - The element to be visible.
- * @param {Object} [spot] - An object with optional top and left properties,
- *   specifying the offset from the top left edge.
- * @param {number} [spot.left]
- * @param {number} [spot.top]
- */
-function scrollIntoView(element, spot) {
-  // Assuming offsetParent is available (it's not available when viewer is in
-  // hidden iframe or object). We have to scroll: if the offsetParent is not set
-  // producing the error. See also animationStarted.
-  let parent = element.offsetParent;
-  if (!parent) {
-    console.error("offsetParent is not set -- cannot scroll");
-    return;
-  }
-  let offsetY = element.offsetTop + element.clientTop;
-  let offsetX = element.offsetLeft + element.clientLeft;
-  while (
-    parent.clientHeight === parent.scrollHeight &&
-    parent.clientWidth === parent.scrollWidth
-  ) {
-    offsetY += parent.offsetTop;
-    offsetX += parent.offsetLeft;
-
-    parent = parent.offsetParent;
-    if (!parent) {
-      return; // no need to scroll
-    }
-  }
-  if (spot) {
-    if (spot.top !== undefined) {
-      offsetY += spot.top;
-    }
-    if (spot.left !== undefined) {
-      offsetX += spot.left;
-      parent.scrollLeft = offsetX;
-    }
-  }
-  parent.scrollTop = offsetY;
-}
-
 /**
  * Helper function to start monitoring the scroll event and converting them into
  * PDF.js friendly one: with scroll debounce and scroll direction.
@@ -890,7 +847,6 @@ export {
   ProgressBar,
   removeNullCharacters,
   SCROLLBAR_PADDING,
-  scrollIntoView,
   ScrollMode,
   SidebarView,
   SpreadMode,