From 057be3722a29cdbab46b631f5e209d5c4bee64dc Mon Sep 17 00:00:00 2001
From: Jules Youngberg <jules@wanderlog.com>
Date: Fri, 12 Jun 2026 11:23:41 -0700
Subject: [PATCH 1/3] fix(streamdown): re-render for offset changes in
 components

---
 .../__tests__/components-rerender.test.tsx    | 33 +++++++++++++++++++
 packages/streamdown/lib/components.tsx        |  5 ++-
 2 files changed, 37 insertions(+), 1 deletion(-)

diff --git a/packages/streamdown/__tests__/components-rerender.test.tsx b/packages/streamdown/__tests__/components-rerender.test.tsx
index c0ed0429..6bfbb1a1 100644
--- a/packages/streamdown/__tests__/components-rerender.test.tsx
+++ b/packages/streamdown/__tests__/components-rerender.test.tsx
@@ -422,6 +422,39 @@ describe("sameNodePosition edge cases", () => {
 
     expect(container.querySelector("ol")).toBeTruthy();
   });
+
+  it("should re-render when only offset changes", () => {
+    const nodeV1 = {
+      position: {
+        start: { line: 1, column: 1, offset: 0 },
+        end: { line: 2, column: 5, offset: 20 },
+      },
+    };
+    const nodeV2 = {
+      position: {
+        start: { line: 1, column: 1, offset: 0 },
+        end: { line: 2, column: 5, offset: 35 },
+      },
+    };
+
+    const { container, rerender } = render(
+      <ReRenderWrapper count={0}>
+        <Ol node={nodeV1 as any}>
+          <li>item</li>
+        </Ol>
+      </ReRenderWrapper>
+    );
+
+    rerender(
+      <ReRenderWrapper count={1}>
+        <Ol node={nodeV2 as any}>
+          <li>item</li>
+        </Ol>
+      </ReRenderWrapper>
+    );
+
+    expect(container.querySelector("ol")).toBeTruthy();
+  });
 });
 
 describe("MemoParagraph block code unwrapping with data-block", () => {
diff --git a/packages/streamdown/lib/components.tsx b/packages/streamdown/lib/components.tsx
index 2449ca3a..8f0c33ad 100644
--- a/packages/streamdown/lib/components.tsx
+++ b/packages/streamdown/lib/components.tsx
@@ -42,6 +42,7 @@ const LANGUAGE_REGEX = /language-([^\s]+)/;
 interface MarkdownPoint {
   column?: number;
   line?: number;
+  offset?: number;
 }
 interface MarkdownPosition {
   end?: MarkdownPoint;
@@ -74,8 +75,10 @@ function sameNodePosition(prev?: MarkdownNode, next?: MarkdownNode): boolean {
   return (
     prevStart?.line === nextStart?.line &&
     prevStart?.column === nextStart?.column &&
+    prevStart?.offset === nextStart?.offset &&
     prevEnd?.line === nextEnd?.line &&
-    prevEnd?.column === nextEnd?.column
+    prevEnd?.column === nextEnd?.column &&
+    prevEnd?.offset === nextEnd?.offset
   );
 }
 

From 7899ea9125c186076cd879d752c0c20486219550 Mon Sep 17 00:00:00 2001
From: Jules Youngberg <jules@wanderlog.com>
Date: Fri, 12 Jun 2026 12:28:56 -0700
Subject: [PATCH 2/3] add changeset

---
 .changeset/fair-balloons-share.md | 5 +++++
 1 file changed, 5 insertions(+)
 create mode 100644 .changeset/fair-balloons-share.md

diff --git a/.changeset/fair-balloons-share.md b/.changeset/fair-balloons-share.md
new file mode 100644
index 00000000..0d971813
--- /dev/null
+++ b/.changeset/fair-balloons-share.md
@@ -0,0 +1,5 @@
+---
+"streamdown": patch
+---
+
+Compare position.start.offset and position.end.offset in sameNodePosition so mid-block markdown updates aren't skipped by React.memo.

From ab93808357b9897934174ff990ed2ad6a352f27b Mon Sep 17 00:00:00 2001
From: Jules Youngberg <jules@wanderlog.com>
Date: Fri, 12 Jun 2026 12:53:17 -0700
Subject: [PATCH 3/3] update changeset

---
 .changeset/fair-balloons-share.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.changeset/fair-balloons-share.md b/.changeset/fair-balloons-share.md
index 0d971813..f3f6a75c 100644
--- a/.changeset/fair-balloons-share.md
+++ b/.changeset/fair-balloons-share.md
@@ -2,4 +2,4 @@
 "streamdown": patch
 ---
 
-Compare position.start.offset and position.end.offset in sameNodePosition so mid-block markdown updates aren't skipped by React.memo.
+Fix stale rendering when in-block markdown content changes during streaming updates.