fix(code-block): use absolute positioning for action buttons to fix clicks in nested scroll containers

.changeset/fix-code-block-buttons-absolute.md

@@ -0,0 +1,13 @@
+---
+"streamdown": patch
+---
+
+fix(code-block): use absolute positioning for action buttons to fix click events in nested scroll containers
+
+Switches the code block action button wrapper from `position: sticky` to
+`position: absolute` (with `position: relative` on the container) so that
+hit-testing works correctly in layouts with multiple nested `overflow: auto`
+scroll containers. Previously, the `sticky` + `pointer-events-none/auto`
+pattern caused browsers to mis-route click events to the code block wrapper
+rather than the buttons when the component was embedded in 2+ nested scroll
+containers.

packages/streamdown/lib/code-block/container.tsx

@@ -18,7 +18,7 @@ export const CodeBlockContainer = ({
   return (
     <div
       className={cn(
-        "my-4 flex w-full flex-col gap-2 rounded-xl border border-border bg-sidebar p-2",
+        "relative my-4 flex w-full flex-col gap-2 rounded-xl border border-border bg-sidebar p-2",
         className
       )}
       data-incomplete={isIncomplete || undefined}

packages/streamdown/lib/code-block/index.tsx

@@ -70,7 +70,7 @@ export const CodeBlock = ({
         {children ? (
           <div
             className={cn(
-              "pointer-events-none sticky top-2 z-10 -mt-10 flex h-8 items-center justify-end"
+              "pointer-events-none absolute top-2 right-2 z-10 flex items-center"
             )}
           >
             <div