⚡ perf(vscode): 代码阅读预览屏幕外的顶层块跳过样式、排版和绘制（content-visibility），没画过的按内容估的高度占位；跳到某一行、恢复滚动位置、跳到改动和定义前先把目标那一带照常排版再量，滚过去位置不变

vscode/webview-ui/src/codeReader/BlockTree.tsx

@@ -13,6 +13,7 @@ import { BlockTools } from './BlockTools'
 import { CodeEditor } from './CodeEditor'
 import { DiffText } from './DiffText'
 import { removedTitle } from './diffView'
+import { estimatedHeight } from './itemHeight'
 import { KindIcon } from './kindIcons'
 import { PropertyGrid, PropertyItems, PropertyTable } from './PropertyGrid'
 import { chatOf, EMPTY_CHAT, sameChat, unfinished } from './qa'
@@ -303,7 +304,7 @@ const BlockItem = memo(({ block, item }: { block: BlockView, item: boolean }): R
     <>
       {shape.run !== undefined && <UnchangedStrip count={shape.run} onOpen={() => tree.onOpenRun(block.id)} />}
       {shape.shown && (
-        <Item item={item} line={block.startLine}>
+        <Item item={item} line={block.startLine} height={item ? estimatedHeight(block, shape.open) : 0}>
           <BlockCard block={block} shape={shape} ask={ask} rewrite={rewriting} />
           {/* 输入框、展开状态跟着块的记号走，文档刷新块 id 变了也不丢 */}
           {qa && ask.chat && (
@@ -344,11 +345,14 @@ const BlockItem = memo(({ block, item }: { block: BlockView, item: boolean }): R
 })
 BlockItem.displayName = 'BlockItem'
 
-/** 顶层一块的外层（见 BlockTree 的 items）；不套时原样 */
-function Item({ item, line, children }: { item: boolean, line: number, children: ReactNode }): ReactElement {
+/**
+ * 顶层一块的外层（见 BlockTree 的 items）；不套时原样。离视口远时浏览器跳过它里面的样式、排版和绘制（.cr-item 的 content-visibility），
+ * 没画过时按估的高度（height，见 estimatedHeight）占位，画过一次就记住真实高度。
+ */
+function Item({ item, line, height, children }: { item: boolean, line: number, height: number, children: ReactNode }): ReactElement {
   if (!item)
     return <>{children}</>
-  return <div className="cr-item flex flex-col gap-2" data-line={line}>{children}</div>
+  return <div className="cr-item flex flex-col gap-2" data-line={line} style={{ containIntrinsicBlockSize: `auto ${height}px` }}>{children}</div>
 }
 
 /**