Show right sidebar focus without adding layout padding

Sources/RightSidebarPanelView.swift

@@ -82,6 +82,7 @@ struct RightSidebarPanelView: View {
         guard let responder = window.firstResponder else { return false }
         return AppDelegate.shared?.isRightSidebarFocusResponder(responder, in: window) == true
     }
+    @Environment(\.cmuxAccentColor) private var cmuxAccent
     @State private var focusShortcutHintMonitor = WindowScopedShortcutHintModifierMonitor(activation: .commandOnly)
     @State private var closeShortcutHintMonitor = WindowScopedShortcutHintModifierMonitor(activation: .commandOnly)
     @State private var hasMountedRightSidebarContent = false
@@ -162,6 +163,12 @@ struct RightSidebarPanelView: View {
     }
 
     var body: some View {
+        // Share the content clip and focus stroke without adding layout space.
+        let boundary = UnevenRoundedRectangle(
+            bottomTrailingRadius: 16,
+            topTrailingRadius: 16,
+            style: .continuous
+        )
         VStack(spacing: 0) {
             modeBar
                 .rightSidebarChromeBottomBorder(
@@ -170,6 +177,17 @@ struct RightSidebarPanelView: View {
             contentForMode
                 .frame(maxWidth: .infinity, maxHeight: .infinity)
         }
+        .clipShape(boundary)
+        .overlay {
+            boundary
+                .strokeBorder(
+                    Color(nsColor: cmuxAccent.nsColor(isDark: windowAppearance.resolvedColorScheme == .dark)),
+                    lineWidth: 1
+                )
+                .opacity(fileExplorerState.rightSidebarOwnsInputFocus ? 1 : 0)
+                .allowsHitTesting(false)
+                .accessibilityHidden(true)
+        }
         .rightSidebarButtonBorderShape()
         .frame(maxWidth: .infinity, maxHeight: .infinity)
         // Keep every mode (including Dock and AppKit-backed file rows) on the

Sources/WorkspaceContentView.swift

@@ -14,6 +14,13 @@ private enum WorkspaceTitlebarInteractionMetrics {
 }
 
 enum WorkspacePanelVisibilityPolicy {
+    static func mainContentIsFocused(
+        isWorkspaceInputActive: Bool,
+        rightSidebarOwnsInputFocus: Bool
+    ) -> Bool {
+        isWorkspaceInputActive && !rightSidebarOwnsInputFocus
+    }
+
     nonisolated static func panelVisibleInUI(
         isWorkspaceVisible: Bool,
         paneHasSelectedTab: Bool,
@@ -217,7 +224,14 @@ struct WorkspaceContentView: View {
             }
         }()
 
-        let bonsplitView = BonsplitView(controller: workspace.bonsplitController) { tab, paneId in
+        let isMainContentFocused = WorkspacePanelVisibilityPolicy.mainContentIsFocused(
+            isWorkspaceInputActive: isWorkspaceInputActive,
+            rightSidebarOwnsInputFocus: rightSidebarOwnsInputFocus
+        )
+        let bonsplitView = BonsplitView(
+            controller: workspace.bonsplitController,
+            isMainContentFocused: isMainContentFocused
+        ) { tab, paneId in
             // Content for each tab in bonsplit
             let _ = Self.debugPanelLookup(tab: tab, workspace: workspace)
             if let panel = workspace.panel(for: tab.id) {
@@ -229,7 +243,7 @@ struct WorkspaceContentView: View {
                 let isFocusedPanel = isWorkspaceInputActive && workspace.focusedPanelId == panel.id
                 // Gated focus for the ring/active state only: the main pane yields
                 // its focus ring while the right sidebar (Dock) owns focus.
-                let isFocused = isFocusedPanel && !rightSidebarOwnsInputFocus
+                let isFocused = isMainContentFocused && workspace.focusedPanelId == panel.id
                 let selectedTab = workspace.bonsplitController.selectedTab(inPane: paneId)
                 let isSelectedInPane = selectedTab?.id == tab.id
                 let isVisibleInUI = Self.panelVisibleInUI(

cmuxTests/WorkspaceContentViewVisibilityTests.swift

@@ -655,6 +655,28 @@ final class WorkspaceContentViewVisibilityTests {
         )
     }
 
+    @Test
+    func mainContentFocusYieldsToRightSidebarWithoutChangingWorkspaceVisibility() {
+        #expect(
+            WorkspacePanelVisibilityPolicy.mainContentIsFocused(
+                isWorkspaceInputActive: true,
+                rightSidebarOwnsInputFocus: false
+            )
+        )
+        #expect(
+            !WorkspacePanelVisibilityPolicy.mainContentIsFocused(
+                isWorkspaceInputActive: true,
+                rightSidebarOwnsInputFocus: true
+            )
+        )
+        #expect(
+            !WorkspacePanelVisibilityPolicy.mainContentIsFocused(
+                isWorkspaceInputActive: false,
+                rightSidebarOwnsInputFocus: false
+            )
+        )
+    }
+
     @Test
     func testRenderedVisiblePanelPolicyPrefersSelectedTabOverStaleFocusedPanel() {
         let paneId = UUID()