diff --git a/apps/mobile/modules/t3-review-diff/ios/T3ReviewDiffModule.swift b/apps/mobile/modules/t3-review-diff/ios/T3ReviewDiffModule.swift
index 96a1785f9fc644ad945bdae6c17a5ee1e6d0dd67..5564dce34af30cd3901afbdfd242983b1d1feabf 100644
--- a/apps/mobile/modules/t3-review-diff/ios/T3ReviewDiffModule.swift
+++ b/apps/mobile/modules/t3-review-diff/ios/T3ReviewDiffModule.swift
@@ -49,6 +49,14 @@ public class T3ReviewDiffModule: Module {
         view.setContentWidth(CGFloat(contentWidth))
       }
 
+      Prop("contentInsetTop") { (view: T3ReviewDiffView, inset: Double) in
+        view.setContentInsetTop(CGFloat(inset))
+      }
+
+      Prop("contentInsetBottom") { (view: T3ReviewDiffView, inset: Double) in
+        view.setContentInsetBottom(CGFloat(inset))
+      }
+
       Prop("initialRowIndex") { (view: T3ReviewDiffView, initialRowIndex: Double) in
         view.setInitialRowIndex(initialRowIndex)
       }
diff --git a/apps/mobile/modules/t3-review-diff/ios/T3ReviewDiffView.swift b/apps/mobile/modules/t3-review-diff/ios/T3ReviewDiffView.swift
index 928e3b5669d1840c44f5978eca7f496c475047e5..dfddaf7016c364736629d8c9059311d6bace0d0f 100644
--- a/apps/mobile/modules/t3-review-diff/ios/T3ReviewDiffView.swift
+++ b/apps/mobile/modules/t3-review-diff/ios/T3ReviewDiffView.swift
@@ -563,6 +563,24 @@ public final class T3ReviewDiffView: ExpoView, UIScrollViewDelegate {
     ])
   }
 
+  // Source files fill the screen so UIKit can sample content below the glass bar.
+  // Keep the same visible row when header or safe-area reservations change.
+  func setContentInsetTop(_ inset: CGFloat) {
+    scrollView.automaticallyAdjustsScrollIndicatorInsets = false
+    let inset = max(0, inset)
+    let delta = inset - scrollView.contentInset.top
+    guard delta != 0 else { return }
+    scrollView.contentInset.top = inset
+    scrollView.verticalScrollIndicatorInsets.top = inset
+    scrollView.contentOffset.y -= delta
+    updateViewportFrame()
+  }
+
+  func setContentInsetBottom(_ inset: CGFloat) {
+    scrollView.contentInset.bottom = max(0, inset)
+    scrollView.verticalScrollIndicatorInsets.bottom = max(0, inset)
+  }
+
   func setContentResetKey(_ contentResetKey: String) {
     guard contentResetKey != self.contentResetKey else {
       return
@@ -577,7 +595,7 @@ public final class T3ReviewDiffView: ExpoView, UIScrollViewDelegate {
     hasAppliedInitialRowIndex = false
     pendingScrollFileId = nil
     isProgrammaticScrollActive = false
-    scrollView.setContentOffset(.zero, animated: false)
+    scrollView.setContentOffset(CGPoint(x: 0, y: -scrollView.contentInset.top), animated: false)
     updateContentMetrics()
     updateViewportFrame()
     lastVisibleFileId = nil
@@ -870,8 +888,12 @@ public final class T3ReviewDiffView: ExpoView, UIScrollViewDelegate {
   }
 
   private func setVerticalContentOffset(_ targetOffset: CGFloat, animated: Bool) {
-    let maxOffset = max(scrollView.contentSize.height - scrollView.bounds.height, 0)
-    let clampedOffset = min(max(targetOffset, 0), maxOffset)
+    let topInset = scrollView.contentInset.top
+    let maxOffset = max(
+      scrollView.contentSize.height - scrollView.bounds.height + scrollView.contentInset.bottom,
+      -topInset
+    )
+    let clampedOffset = min(max(targetOffset - topInset, -topInset), maxOffset)
     let shouldAnimate = animated && abs(scrollView.contentOffset.y - clampedOffset) > 0.5
     isProgrammaticScrollActive = shouldAnimate
     contentView.isVerticalScrollActive = shouldAnimate
@@ -889,12 +911,10 @@ public final class T3ReviewDiffView: ExpoView, UIScrollViewDelegate {
       return
     }
 
-    let targetScreenY = max(0, (bounds.height - rowFrame.height) * 0.3)
-    let maxOffset = max(scrollView.contentSize.height - scrollView.bounds.height, 0)
-    let targetOffset = min(max(rowFrame.minY - targetScreenY, 0), maxOffset)
+    let visibleHeight = bounds.height - scrollView.contentInset.top - scrollView.contentInset.bottom
+    let targetScreenY = max(0, (visibleHeight - rowFrame.height) * 0.3)
     hasAppliedInitialRowIndex = true
-    scrollView.setContentOffset(CGPoint(x: 0, y: targetOffset), animated: false)
-    updateViewportFrame()
+    setVerticalContentOffset(rowFrame.minY - targetScreenY, animated: false)
   }
 }
 
diff --git a/apps/mobile/src/Stack.tsx b/apps/mobile/src/Stack.tsx
index b215ba3380700db97bf266d2c972c9ab9f203eea..569bfc11ada9ad6a7f4777a73fe3564656d5a1ec 100644
--- a/apps/mobile/src/Stack.tsx
+++ b/apps/mobile/src/Stack.tsx
@@ -159,7 +159,7 @@ const GLASS_HEADER_OPTIONS: AppScreenOptions = {
 };
 
 // SOLID: opaque sheet-colored header for surfaces whose content scrolls internally
-// (file viewer, terminal, review) — there is nothing for glass to sample there.
+// (terminal, review) — there is nothing for glass to sample there.
 const SOLID_HEADER_OPTIONS: AppScreenOptions = {
   headerBackButtonDisplayMode: "minimal",
   headerBackTitle: "",
@@ -750,7 +750,7 @@ const RootStackConfig = createWorkspaceStackNavigator({
     ThreadFile: createNativeStackScreen({
       screen: ThreadFileScreen,
       linking: `${THREAD_LINKING_PREFIX}/files/:path*`,
-      options: SOLID_HEADER_OPTIONS,
+      options: GLASS_HEADER_OPTIONS,
     }),
     ThreadMcpApp: createNativeStackScreen({
       screen: McpAppFullscreenScreen,
diff --git a/apps/mobile/src/components/ComposerContextSheet.tsx b/apps/mobile/src/components/ComposerContextSheet.tsx
index 208c15268ec1d3b34d0394b88ac9689842cb37f7..4fbc02ab1e4924fbd9a80d7f66aca5fb45b81546 100644
--- a/apps/mobile/src/components/ComposerContextSheet.tsx
+++ b/apps/mobile/src/components/ComposerContextSheet.tsx
@@ -47,6 +47,7 @@ function ContextField(props: { label: string; value: string | null | undefined;
           style={{ height: Math.min(260, Math.max(100, props.value.split("\n").length * 22 + 36)) }}
         >
           <SourceFileSurface
+            embedded
             contents={props.value}
             path={props.label === "HTML" ? "element.html" : "styles.css"}
           />
diff --git a/apps/mobile/src/features/diffs/nativeReviewDiffSurface.ts b/apps/mobile/src/features/diffs/nativeReviewDiffSurface.ts
index fda73410668731e282c8a4895462dbf12d751946..16208a7d5a2dd90d1291e23c48f2ae40955b00ec 100644
--- a/apps/mobile/src/features/diffs/nativeReviewDiffSurface.ts
+++ b/apps/mobile/src/features/diffs/nativeReviewDiffSurface.ts
@@ -121,6 +121,8 @@ export interface NativeReviewDiffViewProps extends ViewProps {
   readonly styleJson?: string;
   readonly rowHeight: number;
   readonly contentWidth: number;
+  readonly contentInsetTop?: number;
+  readonly contentInsetBottom?: number;
   readonly initialRowIndex?: number;
   readonly refreshing?: boolean;
   readonly nativeViewRef?: Ref<NativeReviewDiffViewHandle>;
diff --git a/apps/mobile/src/features/files/FileTreeBrowser.tsx b/apps/mobile/src/features/files/FileTreeBrowser.tsx
index ed42f5345abe7ef7eea3f6f360415624dda47d52..4d313b47b49fcb851c58b95898f78fa1ac2d8129 100644
--- a/apps/mobile/src/features/files/FileTreeBrowser.tsx
+++ b/apps/mobile/src/features/files/FileTreeBrowser.tsx
@@ -8,7 +8,7 @@ import { useSafeAreaInsets } from "react-native-safe-area-context";
 import { AppText as Text } from "../../components/AppText";
 import { PierreEntryIcon } from "../../components/PierreEntryIcon";
 import { cn } from "../../lib/cn";
-import { IOS_NAV_BAR_HEIGHT } from "../../lib/layoutMetrics";
+import { useNativeColumnLayoutMetrics } from "../../native/native-layout-metrics";
 import {
   buildFileTree,
   flattenFileTree,
@@ -42,7 +42,6 @@ const FileTreeRow = memo(function FileTreeRow(props: {
   readonly item: VisibleFileTreeNode;
   readonly selected: boolean;
   readonly expanded: boolean;
-  readonly loaded: boolean;
   readonly loading: boolean;
   readonly onPressDirectory: (path: string, expand: boolean) => void;
   readonly onPreviewFile?: (path: string) => void;
@@ -98,10 +97,6 @@ const FileTreeRow = memo(function FileTreeRow(props: {
       </Text>
       {node.kind === "directory" && props.expanded && props.loading ? (
         <ActivityIndicator size="small" accessibilityLabel={`Loading ${node.name}`} />
-      ) : node.kind === "directory" && props.loaded ? (
-        <Text className="text-2xs font-t3-medium text-foreground-tertiary">
-          {node.children.length}
-        </Text>
       ) : null}
     </Pressable>
   );
@@ -115,7 +110,6 @@ export function FileTreeBrowser(props: {
   readonly searchQuery: string;
   readonly searchTruncated: boolean;
   readonly selectedPath: string | null;
-  readonly loadedDirectories: ReadonlySet<string>;
   readonly loadingDirectories: ReadonlySet<string>;
   readonly onLoadDirectory: (path: string) => void;
   readonly onPreviewFile?: (path: string) => void;
@@ -128,14 +122,12 @@ export function FileTreeBrowser(props: {
     readonly selectedPathAtPress: string | null;
   } | null>(null);
   const insets = useSafeAreaInsets();
-  // Native transparent-header height ≈ safe-area top + nav bar (~44). Matches the
-  // observed adjustedContentInset bottom (~102) seen in the native trace.
-  const headerInset = Platform.OS === "ios" ? insets.top + IOS_NAV_BAR_HEIGHT : 0;
+  const columnMetrics = useNativeColumnLayoutMetrics();
+  const headerInset = Platform.OS === "ios" ? (columnMetrics?.safeArea.top ?? insets.top) : 0;
   const {
     onLoadDirectory,
     onPreviewFile,
     onSelectFile,
-    loadedDirectories,
     loadingDirectories,
     selectedPath: controlledSelectedPath,
   } = props;
@@ -226,7 +218,6 @@ export function FileTreeBrowser(props: {
         item={item}
         selected={item.node.kind === "file" && item.node.path === selectedPath}
         expanded={expandedPaths.has(item.node.path)}
-        loaded={loadedDirectories.has(item.node.path)}
         loading={loadingDirectories.has(item.node.path)}
         onPressDirectory={toggleDirectory}
         onPreviewFile={onPreviewFile}
@@ -237,7 +228,6 @@ export function FileTreeBrowser(props: {
       expandedPaths,
       handleSelectFile,
       onPreviewFile,
-      loadedDirectories,
       loadingDirectories,
       selectedPath,
       toggleDirectory,
@@ -245,8 +235,8 @@ export function FileTreeBrowser(props: {
   );
 
   const extraData = useMemo(
-    () => ({ expandedPaths, loadedDirectories, loadingDirectories, selectedPath }),
-    [expandedPaths, loadedDirectories, loadingDirectories, selectedPath],
+    () => ({ expandedPaths, loadingDirectories, selectedPath }),
+    [expandedPaths, loadingDirectories, selectedPath],
   );
 
   // UIKit owns the header inset on every supported iOS version. Keep the
@@ -259,9 +249,7 @@ export function FileTreeBrowser(props: {
       data={visibleNodes}
       keyExtractor={(item) => item.node.path}
       contentInsetAdjustmentBehavior={Platform.OS === "ios" ? "automatic" : "never"}
-      scrollIndicatorInsets={
-        Platform.OS === "ios" ? { top: headerInset, left: 0, right: 0, bottom: 0 } : undefined
-      }
+      automaticallyAdjustsScrollIndicatorInsets={Platform.OS === "ios"}
       keyboardDismissMode="on-drag"
       keyboardShouldPersistTaps="handled"
       estimatedItemSize={42}
diff --git a/apps/mobile/src/features/files/SourceFileSurface.tsx b/apps/mobile/src/features/files/SourceFileSurface.tsx
index 42b7dbf282d4c2fb659562059ef526e20a77e704..928da8b0f5435dea452ed8d59a16535e46407aeb 100644
--- a/apps/mobile/src/features/files/SourceFileSurface.tsx
+++ b/apps/mobile/src/features/files/SourceFileSurface.tsx
@@ -11,9 +11,10 @@ import {
   useWindowDimensions,
   View,
 } from "react-native";
-
+import { useSafeAreaInsets } from "react-native-safe-area-context";
 import { AppText as Text } from "../../components/AppText";
 import { LoadingStrip } from "../../components/LoadingStrip";
+import { useNativeColumnLayoutMetrics } from "../../native/native-layout-metrics";
 import {
   type NativeReviewDiffViewProps,
   resolveNativeReviewDiffView,
@@ -39,7 +40,11 @@ import { sourceHighlightAtom } from "./sourceHighlightingState";
 interface SourceFileSurfaceProps {
   readonly contents: string;
   readonly path: string;
+  /** The enclosing sheet or card already reserves its own chrome and safe area. */
+  readonly embedded?: boolean;
   readonly initialLine?: number | null;
+  /** Override when a fixed notice already reserves the native header. */
+  readonly headerInsetTop?: number;
   /** Keep the entire document in one native text-selection scope. */
   readonly selectable?: boolean;
   /** Enables native pull-to-refresh on the source surface. */
@@ -184,6 +189,9 @@ function NativeSourceFileSurface(
   },
 ) {
   const { NativeView, onRefresh } = props;
+  const insets = useSafeAreaInsets();
+  const columnMetrics = useNativeColumnLayoutMetrics();
+  const safeArea = columnMetrics?.safeArea ?? insets;
   const { codeSurface, codeWordBreak, nativeSourceStyle } = useAppearanceCodeSurface();
   const { themeAppearance, themeId } = useAppearancePreferences();
   const appTheme = useUniwindTheme();
@@ -214,6 +222,8 @@ function NativeSourceFileSurface(
         appearanceScheme={themeAppearance}
         contentResetKey={props.path}
         contentWidth={contentWidth}
+        contentInsetTop={props.embedded ? 0 : (props.headerInsetTop ?? safeArea.top)}
+        contentInsetBottom={props.embedded ? 0 : safeArea.bottom + 8}
         initialRowIndex={targetIndex ?? -1}
         rowHeight={nativeSourceStyle.rowHeight ?? codeSurface.rowHeight}
         rowsJson={rowsJson}
@@ -233,6 +243,7 @@ function NativeSourceFileSurface(
 }
 
 function JavaScriptSourceFileSurface(props: SourceFileSurfaceProps) {
+  const usesAutomaticInsets = Platform.OS === "ios" && !props.embedded;
   const foreground = useUniwindTheme()["--color-foreground"];
   const { codeSurface, codeWordBreak } = useAppearanceCodeSurface();
   const { normalizedContents, lines, status, targetIndex, tokens } = useSourceFileModel(props);
@@ -323,6 +334,8 @@ function JavaScriptSourceFileSurface(props: SourceFileSurfaceProps) {
   const list = (
     <FlatList
       ref={listRef}
+      contentInsetAdjustmentBehavior={usesAutomaticInsets ? "automatic" : "never"}
+      automaticallyAdjustsScrollIndicatorInsets={usesAutomaticInsets}
       refreshControl={refreshControl}
       data={lines}
       keyExtractor={(_line, index) => String(index)}
@@ -354,6 +367,8 @@ function JavaScriptSourceFileSurface(props: SourceFileSurfaceProps) {
     <ScrollView
       refreshControl={refreshControl}
       className="flex-1"
+      contentInsetAdjustmentBehavior={usesAutomaticInsets ? "automatic" : "never"}
+      automaticallyAdjustsScrollIndicatorInsets={usesAutomaticInsets}
       contentContainerStyle={{
         paddingBottom: codeSurface.rowHeight,
         paddingHorizontal: 12,
@@ -393,9 +408,11 @@ export function SourceFileSurface(props: SourceFileSurfaceProps) {
   // The native canvas draws source lines without text selection or wrapping. Attachments
   // need one selectable text view in either wrap mode; workspace line navigation can still
   // use the canvas when wrapping is disabled.
-  return NativeView && !codeWordBreak && !props.selectable ? (
-    <NativeSourceFileSurface {...props} NativeView={NativeView} />
-  ) : (
-    <JavaScriptSourceFileSurface {...props} />
-  );
+  const surface =
+    NativeView && !codeWordBreak && !props.selectable ? (
+      <NativeSourceFileSurface {...props} NativeView={NativeView} />
+    ) : (
+      <JavaScriptSourceFileSurface {...props} />
+    );
+  return surface;
 }
diff --git a/apps/mobile/src/features/files/ThreadFilesRouteScreen.tsx b/apps/mobile/src/features/files/ThreadFilesRouteScreen.tsx
index 6c8cac046bb20aa9f18e634f8672d320ef9f81eb..ca9adeaea165093f4522a240ca92ef464bc45d42 100644
--- a/apps/mobile/src/features/files/ThreadFilesRouteScreen.tsx
+++ b/apps/mobile/src/features/files/ThreadFilesRouteScreen.tsx
@@ -48,6 +48,7 @@ import { FileTreeBrowser } from "./FileTreeBrowser";
 import { useFileTreeEntries } from "./useFileTreeEntries";
 import { preloadWorkspaceFileContents } from "./preload-workspace-file";
 import { SourceFileSurface } from "./SourceFileSurface";
+import { useNativeColumnLayoutMetrics } from "../../native/native-layout-metrics";
 import { ThreadFileNavigatorPane } from "./thread-file-navigator-pane";
 import { ScreenHeader } from "../../components/ScreenHeader";
 import { WorkspaceFileImagePreview } from "./WorkspaceFileImagePreview";
@@ -229,6 +230,10 @@ function FileContent(props: {
 }) {
   // Reopening a mutable host file must not reuse a poster from an earlier visit.
   const thumbnailInstanceId = useId();
+  const insets = useSafeAreaInsets();
+  const columnMetrics = useNativeColumnLayoutMetrics();
+  const reservedHeaderInset =
+    Platform.OS === "ios" && props.truncated ? (columnMetrics?.safeArea.top ?? insets.top) : 0;
   const isMarkdown = isMarkdownPreviewFile(props.relativePath);
   const isBrowserFile = isWorkspaceBrowserPreviewPath(props.relativePath);
   const isImageFile = isWorkspaceImagePreviewPath(props.relativePath);
@@ -300,7 +305,7 @@ function FileContent(props: {
   }
 
   return (
-    <View className="flex-1 bg-sheet">
+    <View className="flex-1 bg-sheet" style={{ paddingTop: reservedHeaderInset }}>
       {props.truncated ? (
         <FilePreviewNotice title="Partial file">
           Preview limited to the first 1 MB of a truncated file.
@@ -320,6 +325,7 @@ function FileContent(props: {
           contents={props.fileContents}
           path={props.relativePath}
           initialLine={props.initialLine}
+          headerInsetTop={props.truncated ? 0 : undefined}
           onRefresh={props.onRefresh}
         />
       )}
@@ -561,7 +567,6 @@ export function ThreadFilesTreeScreen(props: ThreadFilesRouteScreenProps) {
         <FileTreeBrowser
           key={JSON.stringify([environmentId, cwd])}
           entries={entriesQuery.entries}
-          loadedDirectories={entriesQuery.loadedDirectories}
           loadingDirectories={entriesQuery.loadingDirectories}
           onLoadDirectory={entriesQuery.loadDirectory}
           error={entriesQuery.error}
diff --git a/apps/mobile/src/features/files/thread-file-navigator-pane.tsx b/apps/mobile/src/features/files/thread-file-navigator-pane.tsx
index 998c23b1e3001a1358b9df0061df1b83d7e5e040..9ee450edfed284f0c501301c0a4241287b96510d 100644
--- a/apps/mobile/src/features/files/thread-file-navigator-pane.tsx
+++ b/apps/mobile/src/features/files/thread-file-navigator-pane.tsx
@@ -87,7 +87,6 @@ export function ThreadFileNavigatorPane(props: {
     <FileTreeBrowser
       key={JSON.stringify([props.environmentId, props.cwd])}
       entries={entriesQuery.entries}
-      loadedDirectories={entriesQuery.loadedDirectories}
       loadingDirectories={entriesQuery.loadingDirectories}
       onLoadDirectory={entriesQuery.loadDirectory}
       error={