diff --git a/docs/reference/react-performance-audit.md b/docs/reference/react-performance-audit.md
index 6d697227f..2cf9b3f3c 100644
--- a/docs/reference/react-performance-audit.md
+++ b/docs/reference/react-performance-audit.md
@@ -47,7 +47,7 @@ Initial inventory:
 
 ## Coverage Ledger
 
-Current count after low-risk PRs #3038, #3041, #3042, #3044, #3051, #3052, #3053, #3054, #3055, #3056, #3058, #3059, and #3060: 950 Effect hook call sites.
+Current count after low-risk PRs #3038, #3041, #3042, #3044, #3051, #3052, #3053, #3054, #3055, #3056, #3058, #3059, #3060, and #3062: 949 Effect hook call sites.
 
 | Area                           | Files / signal                                                                                           | Scan status                                   | Notes                                                                                                                              |
 | ------------------------------ | -------------------------------------------------------------------------------------------------------- | --------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------- |
@@ -93,6 +93,7 @@ These are candidate batches, not final conclusions. Each item needs code inspect
 | PR S         | Project group dialog open resets                      | Extra render pass from seeding name/delete dialog local state after the dialog opens.                    | `ProjectGroupNameDialog.tsx`, `ProjectGroupDeleteDialog.tsx` covered by #3058                                            | Low            |
 | PR T         | Onboarding agent fallback disclosure                  | Extra render pass from opening the fallback agent list when a selected agent first appears there.         | `AgentStep.tsx` covered by #3059                                                                                         | Low            |
 | PR U         | Feature-wall tour workflow resets                     | Four local reset Effects run after workflow changes or close instead of in the selection/close path.      | `FeatureWallTourSurface.tsx` covered by #3060                                                                            | Low            |
+| PR V         | Workspace board selection pruning                     | Local kanban selection is repaired in an Effect after the drawer closes or board rows change.             | `use-workspace-kanban-selection.ts` covered by #3062                                                                     | Low            |
 
 ## Merge Risk Scale
 
@@ -119,6 +120,7 @@ These are candidate batches, not final conclusions. Each item needs code inspect
 | #3058 | `nwparker/react-perf-project-group-dialogs` | Project group dialogs reset local open-state during render              | Low  | Merged | `pnpm exec oxlint src/renderer/src/components/sidebar/ProjectGroupDeleteDialog.tsx src/renderer/src/components/sidebar/ProjectGroupNameDialog.tsx`; `pnpm run typecheck:web`. |
 | #3059 | `nwparker/react-perf-agent-step-latch` | Onboarding agent fallback disclosure latch updates during render        | Low  | Merged | `pnpm exec oxlint src/renderer/src/components/onboarding/AgentStep.tsx`; `pnpm run typecheck:web`.           |
 | #3060 | `nwparker/react-perf-feature-tour-resets` | Feature-wall tour reset state moves into workflow/close transitions | Low  | Merged | `pnpm exec oxlint src/renderer/src/components/feature-wall/FeatureWallTourSurface.tsx`; `pnpm run typecheck:web`. |
+| #3062 | `nwparker/react-perf-kanban-selection` | Workspace board selection pruning moves out of an Effect          | Low  | Open   | `pnpm exec oxlint src/renderer/src/components/sidebar/use-workspace-kanban-selection.ts`; `pnpm run typecheck:web`. |
 
 ## Reproduction Commands
 
diff --git a/src/renderer/src/components/sidebar/use-workspace-kanban-selection.ts b/src/renderer/src/components/sidebar/use-workspace-kanban-selection.ts
index 0b5efec4c..a73fad197 100644
--- a/src/renderer/src/components/sidebar/use-workspace-kanban-selection.ts
+++ b/src/renderer/src/components/sidebar/use-workspace-kanban-selection.ts
@@ -1,4 +1,4 @@
-import React, { useCallback, useEffect, useMemo, useState } from 'react'
+import React, { useCallback, useMemo, useState } from 'react'
 import type { Worktree } from '../../../../shared/types'
 import {
   areWorktreeSelectionsEqual,
@@ -20,23 +20,24 @@ export function useWorkspaceKanbanSelection(open: boolean, boardWorktrees: reado
     [boardWorktrees, selectedWorktreeIds]
   )
 
-  useEffect(() => {
-    if (!open) {
+  if (!open) {
+    if (selectedWorktreeIds.size > 0) {
       setSelectedWorktreeIds(new Set())
-      setSelectionAnchorId(null)
-      return
     }
-
-    setSelectedWorktreeIds((previous) => {
-      const pruned = pruneWorktreeSelection(previous, selectionAnchorId, boardWorktreeIds)
-      if (pruned.anchorId !== selectionAnchorId) {
-        setSelectionAnchorId(pruned.anchorId)
-      }
-      return areWorktreeSelectionsEqual(previous, pruned.selectedIds)
-        ? previous
-        : pruned.selectedIds
-    })
-  }, [boardWorktreeIds, open, selectionAnchorId])
+    if (selectionAnchorId !== null) {
+      setSelectionAnchorId(null)
+    }
+  } else {
+    const pruned = pruneWorktreeSelection(selectedWorktreeIds, selectionAnchorId, boardWorktreeIds)
+    // Why: the drawer can keep rendering while rows are filtered/reordered.
+    // Prune stale local selection before children see ids that no longer exist.
+    if (!areWorktreeSelectionsEqual(selectedWorktreeIds, pruned.selectedIds)) {
+      setSelectedWorktreeIds(pruned.selectedIds)
+    }
+    if (selectionAnchorId !== pruned.anchorId) {
+      setSelectionAnchorId(pruned.anchorId)
+    }
+  }
 
   const updateSelectionForGesture = useCallback(
     (event: React.MouseEvent<HTMLElement>, worktreeId: string): boolean => {