From d19f893b12bfa35b502e83580daa784109b73e54 Mon Sep 17 00:00:00 2001
From: CosmosJ0618 <CosmosJ0618@gmail.com>
Date: Tue, 30 Jun 2026 23:57:10 +0800
Subject: [PATCH] Marks: fix local marks not restoring position in SPAs

Fix an issue where local marks fail to jump correctly on modern sites (like Twitter/Reddit) that use internal divs instead of the window for scrolling. Marks now save and restore the scroll position of the inner active element.
---
 content_scripts/marks.js    | 22 +++++++++++++++++++++-
 content_scripts/scroller.js |  8 ++++++++
 2 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/content_scripts/marks.js b/content_scripts/marks.js
index 0e08d3b15..d967ba24d 100644
--- a/content_scripts/marks.js
+++ b/content_scripts/marks.js
@@ -20,9 +20,20 @@ const Marks = {
   },
 
   getMarkString() {
+    let localScrollX = 0;
+    let localScrollY = 0;
+    if (globalThis.Scroller) {
+      const scrollableEl = Scroller.activeElement();
+      if (scrollableEl) {
+        localScrollX = scrollableEl.scrollLeft;
+        localScrollY = scrollableEl.scrollTop;
+      }
+    }
     return JSON.stringify({
       scrollX: globalThis.scrollX,
       scrollY: globalThis.scrollY,
+      localScrollX,
+      localScrollY,
       hash: globalThis.location.hash,
     });
   },
@@ -117,10 +128,19 @@ const Marks = {
               if (markString != null) {
                 this.setPreviousPosition();
                 const position = JSON.parse(markString);
-                if (position.hash && (position.scrollX === 0) && (position.scrollY === 0)) {
+                if (position.hash && (position.scrollX === 0) && (position.scrollY === 0) && !position.localScrollX && !position.localScrollY) {
                   globalThis.location.hash = position.hash;
                 } else {
                   globalThis.scrollTo(position.scrollX, position.scrollY);
+                  if ("localScrollX" in position) {
+                    if (globalThis.Scroller) {
+                      const scrollableEl = Scroller.activeElement();
+                      if (scrollableEl) {
+                        scrollableEl.scrollLeft = position.localScrollX;
+                        scrollableEl.scrollTop = position.localScrollY;
+                      }
+                    }
+                  }
                 }
                 this.showMessage("Jumped to local mark", keyChar);
               } else {
diff --git a/content_scripts/scroller.js b/content_scripts/scroller.js
index 5501ed0a7..f1df7cebe 100644
--- a/content_scripts/scroller.js
+++ b/content_scripts/scroller.js
@@ -450,6 +450,14 @@ const Scroller = {
       }
     }
   },
+
+  activeElement() {
+    if (!activatedElement || !document.body.contains(activatedElement)) {
+      activatedElement = (getScrollingElement() && firstScrollableElement()) ||
+        getScrollingElement();
+    }
+    return activatedElement;
+  },
 };
 
 const getSpecialScrollingElement = function () {