fix(tui): coalesce rapid selection copies

packages/tui/src/app.tsx

@@ -571,15 +571,13 @@ function App(props: { pair?: DialogPairCredentials }) {
     offSelectionKeys()
   })
 
-  // Wire up console copy-to-clipboard via opentui's onCopySelection callback
-  renderer.console.onCopySelection = async (text: string) => {
+  // Windows clipboard mutations are serialized by OpenTUI. Coalesce rapid selections here so
+  // they cannot fill its native operation queue and starve renderer polling.
+  const copySelection = Selection.createSelectionCopy(clipboard, toast)
+  renderer.console.onCopySelection = (text: string) => {
     if (!text || text.length === 0) return
 
-    await clipboard
-      .write(text)
-      .then(() => toast.show({ message: "Copied to clipboard", variant: "info" }))
-      .catch(toast.error)
-
+    copySelection(text)
     renderer.clearSelection()
   }
   const terminalTitleEnabled = () => config.data.terminal?.title ?? true

packages/tui/src/util/selection.ts

@@ -23,6 +23,33 @@ type SelectionKeyEvent = {
   stopPropagation: () => void
 }
 
+export function createSelectionCopy(clipboard: ClipboardService, toast: Toast) {
+  let pending: string | undefined
+  let running = false
+
+  const drain = async () => {
+    while (pending !== undefined) {
+      const text = pending
+      pending = undefined
+      const error = await clipboard.write(text).then(
+        () => undefined,
+        (error) => error,
+      )
+      if (pending !== undefined) continue
+      if (error !== undefined) toast.error(error)
+      else toast.show({ message: "Copied to clipboard", variant: "info" })
+    }
+    running = false
+  }
+
+  return (text: string) => {
+    pending = text
+    if (running) return
+    running = true
+    void drain()
+  }
+}
+
 export function copy(renderer: Renderer, toast: Toast, clipboard: ClipboardService): boolean {
   const selection = renderer.getSelection()
   if (!selection) return false

packages/tui/test/selection.test.ts

@@ -0,0 +1,45 @@
+import { expect, test } from "bun:test"
+import { createSelectionCopy } from "../src/util/selection"
+
+test("keeps one clipboard write active and coalesces rapid selections", async () => {
+  const writes: string[] = []
+  const releases: (() => void)[] = []
+  let active = 0
+  let maximumActive = 0
+  const clipboard = {
+    async read() {
+      return undefined
+    },
+    async write(text: string) {
+      writes.push(text)
+      active++
+      maximumActive = Math.max(maximumActive, active)
+      await new Promise<void>((resolve) => releases.push(resolve))
+      active--
+    },
+  }
+  const copied: string[] = []
+  const failed: unknown[] = []
+  const copy = createSelectionCopy(clipboard, {
+    show: (input) => copied.push(input.message),
+    error: (error) => failed.push(error),
+  })
+
+  copy("first")
+  for (let index = 0; index < 100; index++) copy(`selection-${index}`)
+
+  expect(writes).toEqual(["first"])
+  expect(maximumActive).toBe(1)
+
+  releases.shift()?.()
+  await Bun.sleep(0)
+
+  expect(writes).toEqual(["first", "selection-99"])
+  expect(maximumActive).toBe(1)
+
+  releases.shift()?.()
+  await Bun.sleep(0)
+
+  expect(copied).toEqual(["Copied to clipboard"])
+  expect(failed).toEqual([])
+})