diff --git a/docs/audits/terminal-mode-tail-retention/README.md b/docs/audits/terminal-mode-tail-retention/README.md
new file mode 100644
index 00000000000..df5635a6f3a
--- /dev/null
+++ b/docs/audits/terminal-mode-tail-retention/README.md
@@ -0,0 +1,122 @@
+# Retained terminal mode scan tails
+
+The kitty keyboard tracker and daemon mouse-mode mirror retain an incomplete
+escape-sequence tail of at most 4,096 UTF-16 code units. A V8 sliced string can
+keep the entire consumed input alive through that small tail. An ordinary
+split grouped mode sequence, `ESC[?1049;2004;1000;`, is enough: its 18-character
+tail retains each input backing string while its parser stays idle.
+
+The correction copies only accepted incomplete tails through the existing
+`ownRetainedString` helper. Empty/rejected tails and short ESC/CSI prefixes keep
+their existing behavior; the helper leaves strings shorter than 13 code units
+alone. Parser state, live/replay semantics, stack caps, mode flags, and wire
+content are unchanged. These are additional boundaries in
+[#20960](https://github.com/stablyai/orca/pull/20960), alongside the
+[PTY detector carries](../pty-detector-retention/README.md).
+
+## Reproduce
+
+```sh
+ORCA_BACKGROUND_LAUNCH=1 node --expose-gc --max-old-space-size=192 docs/audits/terminal-mode-tail-retention/reproduce.cjs
+```
+
+Run the same script with the installed Electron executable, setting
+`ELECTRON_RUN_AS_NODE=1` and `ORCA_BACKGROUND_LAUNCH=1`, and passing the same
+Node flags. This launches no app window or native PTY. Each run has a 30-second
+deadline and writes either [Node results](./node-results.json) or
+[Electron results](./electron-results.json).
+
+The loader reads the actual five source modules, verifies their fixed hashes,
+reverses only the three copy calls/imports in memory for the baseline, and
+verifies the resulting baseline hashes. All evaluated module and bundle hashes
+are recorded. It needs no Git history, absolute development paths, or ignored
+notes. CRLF source text is normalized before hashing. The parsers and flag
+parser match `v1.4.198`; all five modules match the pre-extension topic
+`8d599520e44654a5c28e9930e3070c00d6499931`, except for these copy calls. This
+tests current dependencies and the selected source modules, not a historical
+application binary. See [source versions](./source-versions.json).
+
+Each runtime checks 42 bounded heap cases: baseline, fixed Buffer copier, and
+fixed Bufferless copier; kitty live/replay, mouse live; 32 distinct 64-Ki-character
+inputs and eight 4-Mi-character inputs; short, complete, oversized, and C1-CSI
+tail controls. Completion must reconstruct the correct modes and release the
+large backing strings. Additional controls preserve replay push idempotence,
+the 16-frame live stack cap, alternate-screen state, snapshot unknownness,
+mouse encodings, and RIS with a trailing partial sequence.
+
+Both runtimes pass all 42 cases. Representative live-path heap deltas in bytes:
+
+| Runtime               | Parser | Input × owners |   Baseline | Buffer copy | Bufferless copy |
+| --------------------- | ------ | -------------- | ---------: | ----------: | --------------: |
+| Node 26               | Kitty  | 64 Ki × 32     |  2,120,952 |      18,376 |           9,480 |
+| Node 26               | Mouse  | 64 Ki × 32     |  2,111,984 |      15,112 |           9,336 |
+| Node 26               | Kitty  | 4 Mi × 8       | 33,557,944 |       3,448 |           3,448 |
+| Node 26               | Mouse  | 4 Mi × 8       | 33,557,072 |       1,312 |           1,312 |
+| Electron 43 / Node 24 | Kitty  | 64 Ki × 32     |  2,111,864 |      12,244 |           5,192 |
+| Electron 43 / Node 24 | Mouse  | 64 Ki × 32     |  2,103,444 |      14,432 |           8,004 |
+| Electron 43 / Node 24 | Kitty  | 4 Mi × 8       | 33,556,316 |       1,884 |           2,604 |
+| Electron 43 / Node 24 | Mouse  | 4 Mi × 8       | 33,556,172 |         776 |             752 |
+
+Heap readings include owner overhead and follow forced GC. The harness clears
+V8's last successful regexp input identically in baseline and fixed cases to
+isolate per-owner storage. That independent process-wide regexp reference can
+keep a most-recent input alive until another successful match; this change does
+not eliminate it. The Bufferless selection is memoized while Buffer is absent,
+then Buffer is restored before measuring; it exercises the actual renderer
+fallback without running a browser renderer.
+
+Two permanent kitty heap regressions fail before the correction at 33,560,832
+and 33,575,040 retained bytes against a 2-MiB limit. They also verify that the
+retained prefix completes correctly and that replay/pop/snapshot state remains
+valid. Existing parser and copier tests provide the wider protocol controls.
+The two mouse regressions likewise fail before the correction at 33,559,240 and
+33,573,200 bytes, and pass afterward with both CSI encodings. The five-suite
+run passes 98 tests, including actual headless-emulator mode snapshots; Node
+and renderer TypeScript checks pass.
+
+## Callers and lifetime
+
+- Kitty renderer panes create or reuse one tracker per pane in
+  `connect-pane-pty.ts:160`. `write-pty-output-to-xterm.ts:23` feeds application
+  output; `apply-reattach-payload.ts` and `hidden-output-seq-and-skip.ts` feed
+  replay. Fresh spawn and exit reset it, and
+  `terminal-pane-pane-closed.ts:69` deletes the map entry. Dashboard previews
+  own another tracker per effect (`AgentTerminalPreview.tsx:116`); cleanup
+  removes its listeners and disposes its terminal.
+- Main's `orca-runtime-capture-provider-terminal-buffer.ts:23` registers
+  temporary live scanners during provider snapshot acquisition and removes
+  them in `finally`. It creates a persistent tracker only after observing an
+  alternate-screen transition (`:48–57`). `orca-runtime-on-pty-data.ts:30`
+  feeds those trackers before later output processing. Exit, floating PTY
+  liveness cleanup, and provider generation reset delete the persistent entry.
+- The daemon does not directly instantiate the kitty tracker, despite its
+  old class comment: its kitty flags come from xterm. No mobile bundle imports
+  this class. Mobile can exercise main-side snapshot acquisition; SSH output
+  can reach main and renderer trackers through the existing provider routes.
+- Mouse mirrors are owned by `HeadlessEmulator` (`headless-emulator.ts:59`).
+  Async writes scan after xterm parses the data (`:190`); synchronous live and
+  cold-restore writes scan at `:224`. Both daemon sessions and main's headless
+  projections use this emulator. It therefore also covers local/remote host
+  emulators serving mobile clients. Emulator disposal stops future writes;
+  eventual owner release removes the mirror. Completing/replacing its tail
+  also releases the old backing string. No ownership or shutdown rule changes.
+
+## Scope and limits
+
+This is a per-owner last-input cost. It does not grow indefinitely with a fixed
+set of parsers and bounded input chunks, and further output often completes or
+replaces the tail. Multiple readers of the same input can share its backing
+storage; do not sum their measurements as independent process memory.
+
+Ordinary daemon bulk frames delivered to main are at most 64 Ki characters
+(`daemon-stream-data-batcher.ts:35`), and ordinary relay output slices are
+16 Ki characters (`relay/pty-handler.ts:343`). Mouse scanning inside the daemon
+happens before outgoing stream framing. The 64-Ki cases demonstrate the issue
+at a normal main-input bound; the 4-Mi cases amplify the mechanism, not a claim
+that ordinary native reads or daemon frames have that size. Replay inputs and
+transformed streams follow their own existing limits. No network, application
+renderer, operating-system PTY, or incident heap was used in this proof.
+
+This reduces retained output in local and SSH paths without changing published
+terminal content. It neither establishes the trigger in #19831/#19768 nor
+explains a reported sustained growth rate or multi-gigabyte incident by itself.
diff --git a/docs/audits/terminal-mode-tail-retention/electron-results.json b/docs/audits/terminal-mode-tail-retention/electron-results.json
new file mode 100644
index 00000000000..e81d9abc27c
--- /dev/null
+++ b/docs/audits/terminal-mode-tail-retention/electron-results.json
@@ -0,0 +1,467 @@
+{
+  "node": "v24.21.0",
+  "electron": "43.7.0",
+  "v8": "15.0.245.31-electron.0",
+  "platform": "darwin",
+  "runnerSha256": "b78dc54a08345732235d4fcc1f72ca1534b00f89280981beda00667d22b8f291",
+  "loaderSha256": "730da9091abba3997432657aef4a2e6e7a3dd0e9218ea78f1838806b6c0fa789",
+  "pendingTailCodeUnits": 18,
+  "clearedRegexStatics": true,
+  "bundles": {
+    "baseline": {
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+      "evaluatedSources": {
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+        "src/shared/terminal-kitty-keyboard-mode-tracker.ts": "2ee0bad47d4575046f71c16e0334a8ae8be531f0cfc67133abc287f8ae5aa403",
+        "src/main/daemon/terminal-mouse-mode-mirror.ts": "5bf8a94ad7ec3fdd151ba7559f49a229b2156818aba88f7b562bef258048acf1",
+        "src/shared/owned-utf16-suffix.ts": "1ca0bb35dfff2d9f3c02caee3d05b0e0c97378df71c878622acf703524d2c475",
+        "src/shared/terminal-kitty-keyboard-flags.ts": "ee8ca63afdca8356fa12878e74973ff92d807aa8d99750b2415b42f4bccb0225"
+      },
+      "sourceVersionsSha256": "29cde88cb882b2d7726a2d4a077484217076090acc009f47a805e368f597e51a"
+    },
+    "fixed-buffer": {
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+        "src/shared/terminal-kitty-keyboard-mode-tracker.ts": "a8da704564b9ab97aa344f380940021d3fa98f80af817751824d14271acb8a84",
+        "src/shared/owned-utf16-suffix.ts": "1ca0bb35dfff2d9f3c02caee3d05b0e0c97378df71c878622acf703524d2c475",
+        "src/shared/terminal-kitty-keyboard-flags.ts": "ee8ca63afdca8356fa12878e74973ff92d807aa8d99750b2415b42f4bccb0225"
+      },
+      "sourceVersionsSha256": "29cde88cb882b2d7726a2d4a077484217076090acc009f47a805e368f597e51a"
+    },
+    "fixed-fallback": {
+      "bundleSha256": "bbae10735fc999eea9dafffcd0e1fc4c47e1a8f1daf0045ed074b08cf3a93d45",
+      "evaluatedSources": {
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+        "src/main/daemon/terminal-mouse-mode-mirror.ts": "e8f4888dabee5c4cc50b0f15584b3b1b5e2da4db1ba25695dd5762ef9c4a6fb3",
+        "src/shared/terminal-kitty-keyboard-mode-tracker.ts": "a8da704564b9ab97aa344f380940021d3fa98f80af817751824d14271acb8a84",
+        "src/shared/owned-utf16-suffix.ts": "1ca0bb35dfff2d9f3c02caee3d05b0e0c97378df71c878622acf703524d2c475",
+        "src/shared/terminal-kitty-keyboard-flags.ts": "ee8ca63afdca8356fa12878e74973ff92d807aa8d99750b2415b42f4bccb0225"
+      },
+      "sourceVersionsSha256": "29cde88cb882b2d7726a2d4a077484217076090acc009f47a805e368f597e51a"
+    }
+  },
+  "reports": [
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+    },
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+    {
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+      "count": 8,
+      "expectedTailLength": 0,
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+    },
+    {
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+    {
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+      "count": 8,
+      "expectedTailLength": 17,
+      "heapDelta": 1884,
+      "afterCompletionDelta": 1652
+    },
+    {
+      "variant": "fixed-fallback",
+      "kind": "mouse",
+      "method": "scan",
+      "inputChars": 65536,
+      "count": 32,
+      "expectedTailLength": 18,
+      "heapDelta": 8004,
+      "afterCompletionDelta": 6992
+    },
+    {
+      "variant": "fixed-fallback",
+      "kind": "mouse",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 18,
+      "heapDelta": 752,
+      "afterCompletionDelta": 508
+    },
+    {
+      "variant": "fixed-fallback",
+      "kind": "mouse",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 2,
+      "heapDelta": 672,
+      "afterCompletionDelta": 1464
+    },
+    {
+      "variant": "fixed-fallback",
+      "kind": "mouse",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 0,
+      "heapDelta": 520,
+      "afterCompletionDelta": 532
+    },
+    {
+      "variant": "fixed-fallback",
+      "kind": "mouse",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 0,
+      "heapDelta": 1548,
+      "afterCompletionDelta": 1560
+    },
+    {
+      "variant": "fixed-fallback",
+      "kind": "mouse",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 17,
+      "heapDelta": 776,
+      "afterCompletionDelta": 544
+    }
+  ]
+}
diff --git a/docs/audits/terminal-mode-tail-retention/load-source.cjs b/docs/audits/terminal-mode-tail-retention/load-source.cjs
new file mode 100644
index 00000000000..fdc39d2b3c6
--- /dev/null
+++ b/docs/audits/terminal-mode-tail-retention/load-source.cjs
@@ -0,0 +1,68 @@
+const assert = require('node:assert/strict')
+const fs = require('node:fs')
+const path = require('node:path')
+const Module = require('node:module')
+const { createHash } = require('node:crypto')
+const { build } = require('esbuild')
+
+const root = path.resolve(__dirname, '../../..')
+const sha = (value) => createHash('sha256').update(value).digest('hex')
+const read = (file) => fs.readFileSync(file, 'utf8').replaceAll('\r\n', '\n')
+const versionsText = read(path.join(__dirname, 'source-versions.json'))
+const versions = JSON.parse(versionsText)
+
+async function loadSource(fixed) {
+  const evaluatedSources = {}
+  const built = await build({
+    stdin: {
+      contents: [
+        "export { TerminalKittyKeyboardModeTracker } from './src/shared/terminal-kitty-keyboard-mode-tracker'",
+        "export { TerminalMouseModeMirror } from './src/main/daemon/terminal-mouse-mode-mirror'",
+        "export { ownRetainedString, resetOwnRetainedStringCopier } from './src/shared/own-retained-string'"
+      ].join('\n'),
+      resolveDir: root
+    },
+    bundle: true,
+    platform: 'node',
+    format: 'cjs',
+    write: false,
+    plugins: [
+      {
+        name: 'hash-fenced-retained-mode-tails',
+        setup(builder) {
+          builder.onLoad({ filter: /\.ts$/ }, ({ path: filename }) => {
+            const relative = path.relative(root, filename).split(path.sep).join('/')
+            const version = versions.sources[relative]
+            assert.ok(version, `Unreviewed source: ${relative}`)
+            let contents = read(filename)
+            assert.equal(sha(contents), version.fixedSha256, `Fixed source changed: ${relative}`)
+            if (!fixed && version.reverse) {
+              for (const { from, to, count } of version.reverse) {
+                assert.equal(contents.split(from).length - 1, count)
+                contents = contents.replaceAll(from, to)
+              }
+            }
+            const expected = fixed ? version.fixedSha256 : version.baselineSha256
+            assert.equal(sha(contents), expected, `Evaluated source changed: ${relative}`)
+            evaluatedSources[relative] = sha(contents)
+            return { contents, loader: 'ts' }
+          })
+        }
+      }
+    ]
+  })
+  assert.deepEqual(Object.keys(evaluatedSources).sort(), Object.keys(versions.sources).sort())
+  const filename = path.join(__dirname, fixed ? 'fixed-bundle.cjs' : 'baseline-bundle.cjs')
+  const loaded = new Module(filename, module)
+  loaded.filename = filename
+  loaded.paths = Module._nodeModulePaths(root)
+  loaded._compile(built.outputFiles[0].text, filename)
+  return {
+    ...loaded.exports,
+    evaluatedSources,
+    bundleSha256: sha(built.outputFiles[0].text),
+    sourceVersionsSha256: sha(versionsText)
+  }
+}
+
+module.exports = { loadSource, sha, read }
diff --git a/docs/audits/terminal-mode-tail-retention/node-results.json b/docs/audits/terminal-mode-tail-retention/node-results.json
new file mode 100644
index 00000000000..e43d49c58df
--- /dev/null
+++ b/docs/audits/terminal-mode-tail-retention/node-results.json
@@ -0,0 +1,467 @@
+{
+  "node": "v26.6.0",
+  "electron": null,
+  "v8": "14.6.202.34-node.26",
+  "platform": "darwin",
+  "runnerSha256": "b78dc54a08345732235d4fcc1f72ca1534b00f89280981beda00667d22b8f291",
+  "loaderSha256": "730da9091abba3997432657aef4a2e6e7a3dd0e9218ea78f1838806b6c0fa789",
+  "pendingTailCodeUnits": 18,
+  "clearedRegexStatics": true,
+  "bundles": {
+    "baseline": {
+      "bundleSha256": "6023f5d6868f5db601f6883acda5d56990d204084a6a3c812799aff1e533a5b0",
+      "evaluatedSources": {
+        "src/shared/own-retained-string.ts": "addea88bc11c725192be2ff617b91315a875113844c95de03e5529cf3d7ef2e2",
+        "src/shared/terminal-kitty-keyboard-mode-tracker.ts": "2ee0bad47d4575046f71c16e0334a8ae8be531f0cfc67133abc287f8ae5aa403",
+        "src/main/daemon/terminal-mouse-mode-mirror.ts": "5bf8a94ad7ec3fdd151ba7559f49a229b2156818aba88f7b562bef258048acf1",
+        "src/shared/owned-utf16-suffix.ts": "1ca0bb35dfff2d9f3c02caee3d05b0e0c97378df71c878622acf703524d2c475",
+        "src/shared/terminal-kitty-keyboard-flags.ts": "ee8ca63afdca8356fa12878e74973ff92d807aa8d99750b2415b42f4bccb0225"
+      },
+      "sourceVersionsSha256": "29cde88cb882b2d7726a2d4a077484217076090acc009f47a805e368f597e51a"
+    },
+    "fixed-buffer": {
+      "bundleSha256": "bbae10735fc999eea9dafffcd0e1fc4c47e1a8f1daf0045ed074b08cf3a93d45",
+      "evaluatedSources": {
+        "src/shared/own-retained-string.ts": "addea88bc11c725192be2ff617b91315a875113844c95de03e5529cf3d7ef2e2",
+        "src/shared/terminal-kitty-keyboard-mode-tracker.ts": "a8da704564b9ab97aa344f380940021d3fa98f80af817751824d14271acb8a84",
+        "src/main/daemon/terminal-mouse-mode-mirror.ts": "e8f4888dabee5c4cc50b0f15584b3b1b5e2da4db1ba25695dd5762ef9c4a6fb3",
+        "src/shared/owned-utf16-suffix.ts": "1ca0bb35dfff2d9f3c02caee3d05b0e0c97378df71c878622acf703524d2c475",
+        "src/shared/terminal-kitty-keyboard-flags.ts": "ee8ca63afdca8356fa12878e74973ff92d807aa8d99750b2415b42f4bccb0225"
+      },
+      "sourceVersionsSha256": "29cde88cb882b2d7726a2d4a077484217076090acc009f47a805e368f597e51a"
+    },
+    "fixed-fallback": {
+      "bundleSha256": "bbae10735fc999eea9dafffcd0e1fc4c47e1a8f1daf0045ed074b08cf3a93d45",
+      "evaluatedSources": {
+        "src/shared/own-retained-string.ts": "addea88bc11c725192be2ff617b91315a875113844c95de03e5529cf3d7ef2e2",
+        "src/main/daemon/terminal-mouse-mode-mirror.ts": "e8f4888dabee5c4cc50b0f15584b3b1b5e2da4db1ba25695dd5762ef9c4a6fb3",
+        "src/shared/terminal-kitty-keyboard-mode-tracker.ts": "a8da704564b9ab97aa344f380940021d3fa98f80af817751824d14271acb8a84",
+        "src/shared/owned-utf16-suffix.ts": "1ca0bb35dfff2d9f3c02caee3d05b0e0c97378df71c878622acf703524d2c475",
+        "src/shared/terminal-kitty-keyboard-flags.ts": "ee8ca63afdca8356fa12878e74973ff92d807aa8d99750b2415b42f4bccb0225"
+      },
+      "sourceVersionsSha256": "29cde88cb882b2d7726a2d4a077484217076090acc009f47a805e368f597e51a"
+    }
+  },
+  "reports": [
+    {
+      "variant": "baseline",
+      "kind": "kitty",
+      "method": "scan",
+      "inputChars": 65536,
+      "count": 32,
+      "expectedTailLength": 18,
+      "heapDelta": 2120952,
+      "afterCompletionDelta": 31112
+    },
+    {
+      "variant": "baseline",
+      "kind": "kitty",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 18,
+      "heapDelta": 33557944,
+      "afterCompletionDelta": 3840
+    },
+    {
+      "variant": "baseline",
+      "kind": "kitty",
+      "method": "scanReplay",
+      "inputChars": 65536,
+      "count": 32,
+      "expectedTailLength": 18,
+      "heapDelta": 2107000,
+      "afterCompletionDelta": 9336
+    },
+    {
+      "variant": "baseline",
+      "kind": "kitty",
+      "method": "scanReplay",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 18,
+      "heapDelta": 33557928,
+      "afterCompletionDelta": 3752
+    },
+    {
+      "variant": "baseline",
+      "kind": "kitty",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 2,
+      "heapDelta": 3320,
+      "afterCompletionDelta": 3288
+    },
+    {
+      "variant": "baseline",
+      "kind": "kitty",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 0,
+      "heapDelta": 3176,
+      "afterCompletionDelta": 4792
+    },
+    {
+      "variant": "baseline",
+      "kind": "kitty",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 0,
+      "heapDelta": 3176,
+      "afterCompletionDelta": 4904
+    },
+    {
+      "variant": "baseline",
+      "kind": "kitty",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 17,
+      "heapDelta": 33557944,
+      "afterCompletionDelta": 3232
+    },
+    {
+      "variant": "baseline",
+      "kind": "mouse",
+      "method": "scan",
+      "inputChars": 65536,
+      "count": 32,
+      "expectedTailLength": 18,
+      "heapDelta": 2111984,
+      "afterCompletionDelta": 13904
+    },
+    {
+      "variant": "baseline",
+      "kind": "mouse",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 18,
+      "heapDelta": 33557072,
+      "afterCompletionDelta": 2272
+    },
+    {
+      "variant": "baseline",
+      "kind": "mouse",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 2,
+      "heapDelta": 1232,
+      "afterCompletionDelta": 1232
+    },
+    {
+      "variant": "baseline",
+      "kind": "mouse",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 0,
+      "heapDelta": 992,
+      "afterCompletionDelta": 1008
+    },
+    {
+      "variant": "baseline",
+      "kind": "mouse",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 0,
+      "heapDelta": 992,
+      "afterCompletionDelta": 1008
+    },
+    {
+      "variant": "baseline",
+      "kind": "mouse",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 17,
+      "heapDelta": 33555840,
+      "afterCompletionDelta": 1048
+    },
+    {
+      "variant": "fixed-buffer",
+      "kind": "kitty",
+      "method": "scan",
+      "inputChars": 65536,
+      "count": 32,
+      "expectedTailLength": 18,
+      "heapDelta": 18376,
+      "afterCompletionDelta": 25472
+    },
+    {
+      "variant": "fixed-buffer",
+      "kind": "kitty",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 18,
+      "heapDelta": 3448,
+      "afterCompletionDelta": 3144
+    },
+    {
+      "variant": "fixed-buffer",
+      "kind": "kitty",
+      "method": "scanReplay",
+      "inputChars": 65536,
+      "count": 32,
+      "expectedTailLength": 18,
+      "heapDelta": 9400,
+      "afterCompletionDelta": 8216
+    },
+    {
+      "variant": "fixed-buffer",
+      "kind": "kitty",
+      "method": "scanReplay",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 18,
+      "heapDelta": 3696,
+      "afterCompletionDelta": 3392
+    },
+    {
+      "variant": "fixed-buffer",
+      "kind": "kitty",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 2,
+      "heapDelta": 3320,
+      "afterCompletionDelta": 3240
+    },
+    {
+      "variant": "fixed-buffer",
+      "kind": "kitty",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 0,
+      "heapDelta": 3176,
+      "afterCompletionDelta": 4648
+    },
+    {
+      "variant": "fixed-buffer",
+      "kind": "kitty",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 0,
+      "heapDelta": 3128,
+      "afterCompletionDelta": 3144
+    },
+    {
+      "variant": "fixed-buffer",
+      "kind": "kitty",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 17,
+      "heapDelta": 3448,
+      "afterCompletionDelta": 3152
+    },
+    {
+      "variant": "fixed-buffer",
+      "kind": "mouse",
+      "method": "scan",
+      "inputChars": 65536,
+      "count": 32,
+      "expectedTailLength": 18,
+      "heapDelta": 15112,
+      "afterCompletionDelta": 14376
+    },
+    {
+      "variant": "fixed-buffer",
+      "kind": "mouse",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 18,
+      "heapDelta": 1312,
+      "afterCompletionDelta": 1008
+    },
+    {
+      "variant": "fixed-buffer",
+      "kind": "mouse",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 2,
+      "heapDelta": 1232,
+      "afterCompletionDelta": 1200
+    },
+    {
+      "variant": "fixed-buffer",
+      "kind": "mouse",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 0,
+      "heapDelta": 992,
+      "afterCompletionDelta": 1008
+    },
+    {
+      "variant": "fixed-buffer",
+      "kind": "mouse",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 0,
+      "heapDelta": 992,
+      "afterCompletionDelta": 1008
+    },
+    {
+      "variant": "fixed-buffer",
+      "kind": "mouse",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 17,
+      "heapDelta": 1344,
+      "afterCompletionDelta": 1048
+    },
+    {
+      "variant": "fixed-fallback",
+      "kind": "kitty",
+      "method": "scan",
+      "inputChars": 65536,
+      "count": 32,
+      "expectedTailLength": 18,
+      "heapDelta": 9480,
+      "afterCompletionDelta": 8216
+    },
+    {
+      "variant": "fixed-fallback",
+      "kind": "kitty",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 18,
+      "heapDelta": 3448,
+      "afterCompletionDelta": 4048
+    },
+    {
+      "variant": "fixed-fallback",
+      "kind": "kitty",
+      "method": "scanReplay",
+      "inputChars": 65536,
+      "count": 32,
+      "expectedTailLength": 18,
+      "heapDelta": 13216,
+      "afterCompletionDelta": 11952
+    },
+    {
+      "variant": "fixed-fallback",
+      "kind": "kitty",
+      "method": "scanReplay",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 18,
+      "heapDelta": 3448,
+      "afterCompletionDelta": 3144
+    },
+    {
+      "variant": "fixed-fallback",
+      "kind": "kitty",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 2,
+      "heapDelta": 3320,
+      "afterCompletionDelta": 3240
+    },
+    {
+      "variant": "fixed-fallback",
+      "kind": "kitty",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 0,
+      "heapDelta": 3176,
+      "afterCompletionDelta": 3192
+    },
+    {
+      "variant": "fixed-fallback",
+      "kind": "kitty",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 0,
+      "heapDelta": 3912,
+      "afterCompletionDelta": 3928
+    },
+    {
+      "variant": "fixed-fallback",
+      "kind": "kitty",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 17,
+      "heapDelta": 3448,
+      "afterCompletionDelta": 3152
+    },
+    {
+      "variant": "fixed-fallback",
+      "kind": "mouse",
+      "method": "scan",
+      "inputChars": 65536,
+      "count": 32,
+      "expectedTailLength": 18,
+      "heapDelta": 9336,
+      "afterCompletionDelta": 8072
+    },
+    {
+      "variant": "fixed-fallback",
+      "kind": "mouse",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 18,
+      "heapDelta": 1312,
+      "afterCompletionDelta": 1008
+    },
+    {
+      "variant": "fixed-fallback",
+      "kind": "mouse",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 2,
+      "heapDelta": 1232,
+      "afterCompletionDelta": 8184
+    },
+    {
+      "variant": "fixed-fallback",
+      "kind": "mouse",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 0,
+      "heapDelta": 992,
+      "afterCompletionDelta": 1008
+    },
+    {
+      "variant": "fixed-fallback",
+      "kind": "mouse",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 0,
+      "heapDelta": 2280,
+      "afterCompletionDelta": 2296
+    },
+    {
+      "variant": "fixed-fallback",
+      "kind": "mouse",
+      "method": "scan",
+      "inputChars": 4194304,
+      "count": 8,
+      "expectedTailLength": 17,
+      "heapDelta": 1312,
+      "afterCompletionDelta": 1016
+    }
+  ]
+}
diff --git a/docs/audits/terminal-mode-tail-retention/reproduce.cjs b/docs/audits/terminal-mode-tail-retention/reproduce.cjs
new file mode 100644
index 00000000000..61801919b7d
--- /dev/null
+++ b/docs/audits/terminal-mode-tail-retention/reproduce.cjs
@@ -0,0 +1,205 @@
+const assert = require('node:assert/strict')
+const fs = require('node:fs')
+const path = require('node:path')
+const { loadSource, sha, read } = require('./load-source.cjs')
+
+assert.equal(process.env.ORCA_BACKGROUND_LAUNCH, '1')
+assert.equal(typeof global.gc, 'function', 'Run with --expose-gc')
+const pending = '\x1b[?1049;2004;1000;'
+const sizes = [
+  [64 * 1024, 32],
+  [4 * 1024 * 1024, 8]
+]
+
+async function heap() {
+  // Isolate owner storage from V8's process-wide last successful regexp input.
+  ;/reset/.test('reset')
+  for (let round = 0; round < 4; round++) {
+    await new Promise((resolve) => setImmediate(resolve))
+    global.gc()
+  }
+  return process.memoryUsage().heapUsed
+}
+
+function createOwner(Owner, method, chars, index, suffix) {
+  const prefix = `${index}:`
+  const data = `${prefix}${'x'.repeat(chars - prefix.length - suffix.length)}${suffix}`
+  const owner = new Owner()
+  owner[method](data)
+  return owner
+}
+
+async function measure(Owner, variant, kind, method, inputChars, count, suffix = pending) {
+  const beforeHeap = await heap()
+  const owners = Array.from({ length: count }, (_, index) =>
+    createOwner(Owner, method, inputChars, index, suffix)
+  )
+  const heapDelta = (await heap()) - beforeHeap
+  const expectedTailLength = suffix.length > 4096 || suffix.endsWith('h') ? 0 : suffix.length
+  assert.ok(owners.every((owner) => owner.scanTail.length === expectedTailLength))
+  const retainsParent = variant === 'baseline' && expectedTailLength >= 13
+  assert.ok(
+    retainsParent ? heapDelta > inputChars * count * 0.75 : heapDelta < 768 * 1024,
+    JSON.stringify({ variant, kind, method, inputChars, count, expectedTailLength, heapDelta })
+  )
+
+  for (const owner of owners) {
+    owner[method]('1006h')
+    if (kind === 'kitty') {
+      if (suffix === pending) {
+        assert.equal(owner.isAlternateScreen, true)
+      }
+      owner[method]('\x1b[>3u')
+      assert.equal(owner.flags, 3)
+      owner.scan('\x1b[<u')
+      assert.equal(owner.flags, 0)
+    } else if (expectedTailLength >= 13) {
+      assert.equal(owner.mouseTrackingMode, 'vt200')
+      assert.equal(owner.sgrMouseMode, true)
+    }
+    assert.equal(owner.scanTail, '')
+  }
+  const afterCompletionDelta = (await heap()) - beforeHeap
+  assert.ok(
+    afterCompletionDelta < 768 * 1024,
+    JSON.stringify({ variant, kind, method, afterCompletionDelta })
+  )
+  for (const owner of owners) {
+    if (kind === 'kitty') {
+      owner.resetForSnapshot()
+      assert.equal(owner.snapshotFlags, undefined)
+    } else {
+      owner.scan('\x1bc')
+      assert.equal(owner.mouseTrackingMode, 'none')
+      assert.equal(owner.sgrMouseMode, false)
+    }
+  }
+  return {
+    variant,
+    kind,
+    method,
+    inputChars,
+    count,
+    expectedTailLength,
+    heapDelta,
+    afterCompletionDelta
+  }
+}
+
+function configureCopier(api, fallback) {
+  api.resetOwnRetainedStringCopier()
+  const originalBuffer = globalThis.Buffer
+  try {
+    if (fallback) {
+      globalThis.Buffer = undefined
+    }
+    assert.equal(api.ownRetainedString(pending), pending)
+  } finally {
+    globalThis.Buffer = originalBuffer
+  }
+}
+
+function behavior(Tracker, Mirror) {
+  const replay = new Tracker()
+  for (let index = 0; index < 70; index++) {
+    replay.scanReplay('\x1b[>3u')
+  }
+  assert.equal(replay.mainStack.length, 0)
+  assert.equal(replay.flags, 3)
+  replay.scan('\x1b[<u')
+  assert.equal(replay.flags, 0)
+  const live = new Tracker()
+  for (let index = 0; index < 70; index++) {
+    live.scan('\x1b[>3u')
+  }
+  assert.equal(live.mainStack.length, 16)
+  live.scan('\x1b[?1049h\x1b[>5u')
+  assert.equal(live.altStack.length, 1)
+  live.scan('\x1b[?1049l')
+  assert.equal(live.flags, 3)
+  live.scan(`\x1bc${pending}`)
+  assert.equal(live.flags, 0)
+  assert.equal(live.scanTail, pending)
+  live.scan('1006h')
+  assert.equal(live.isAlternateScreen, true)
+  live.reset()
+  assert.equal(live.scanTail, '')
+  assert.equal(live.snapshotFlags, 0)
+
+  const mouse = new Mirror()
+  mouse.scan('\x1b[?1003;1016h')
+  assert.equal(mouse.mouseTrackingMode, 'any')
+  assert.equal(mouse.sgrMousePixelsMode, true)
+  mouse.scan('\x9b?1002;1006h')
+  assert.equal(mouse.mouseTrackingMode, 'drag')
+  assert.equal(mouse.sgrMouseMode, true)
+  assert.equal(mouse.sgrMousePixelsMode, false)
+  mouse.scan(`\x1bc${pending}`)
+  assert.equal(mouse.mouseTrackingMode, 'none')
+  assert.equal(mouse.scanTail, pending)
+  mouse.scan('1006h')
+  assert.equal(mouse.mouseTrackingMode, 'vt200')
+  assert.equal(mouse.sgrMouseMode, true)
+}
+
+async function main() {
+  const reports = []
+  const bundles = {}
+  for (const variant of ['baseline', 'fixed-buffer', 'fixed-fallback']) {
+    const api = await loadSource(variant !== 'baseline')
+    const { TerminalKittyKeyboardModeTracker: Tracker, TerminalMouseModeMirror: Mirror } = api
+    bundles[variant] = {
+      bundleSha256: api.bundleSha256,
+      evaluatedSources: api.evaluatedSources,
+      sourceVersionsSha256: api.sourceVersionsSha256
+    }
+    configureCopier(api, variant === 'fixed-fallback')
+    behavior(Tracker, Mirror)
+    for (const [kind, Owner, methods] of [
+      ['kitty', Tracker, ['scan', 'scanReplay']],
+      ['mouse', Mirror, ['scan']]
+    ]) {
+      for (const method of methods) {
+        for (const [chars, count] of sizes) {
+          reports.push(await measure(Owner, variant, kind, method, chars, count))
+        }
+      }
+      for (const suffix of [
+        '\x1b[',
+        '\x1b[?1049;2004;1000;1006h',
+        `\x1b[${'1'.repeat(4095)}`,
+        pending.replace('\x1b[', '\x9b')
+      ]) {
+        reports.push(await measure(Owner, variant, kind, 'scan', 4 * 1024 * 1024, 8, suffix))
+      }
+    }
+  }
+  const report = {
+    node: process.version,
+    electron: process.versions.electron ?? null,
+    v8: process.versions.v8,
+    platform: process.platform,
+    runnerSha256: sha(read(__filename)),
+    loaderSha256: sha(read(path.join(__dirname, 'load-source.cjs'))),
+    pendingTailCodeUnits: pending.length,
+    clearedRegexStatics: true,
+    bundles,
+    reports
+  }
+  const output = path.join(
+    __dirname,
+    `${process.versions.electron ? 'electron' : 'node'}-results.json`
+  )
+  fs.writeFileSync(output, `${JSON.stringify(report, null, 2)}\n`)
+  console.log(
+    JSON.stringify({ output, passed: reports.length, node: report.node, electron: report.electron })
+  )
+}
+main().catch((error) => {
+  console.error(error)
+  process.exitCode = 1
+})
+setTimeout(() => {
+  console.error('fixture deadline')
+  process.exit(2)
+}, 30000).unref()
diff --git a/docs/audits/terminal-mode-tail-retention/source-versions.json b/docs/audits/terminal-mode-tail-retention/source-versions.json
new file mode 100644
index 00000000000..fe29f805765
--- /dev/null
+++ b/docs/audits/terminal-mode-tail-retention/source-versions.json
@@ -0,0 +1,44 @@
+{
+  "publicationTopic": "np-oom-scan-retained-text-slices",
+  "publicationBaseCommit": "8d599520e44654a5c28e9930e3070c00d6499931",
+  "historicalParserRef": "v1.4.198",
+  "historicalScope": "Both parser modules and kitty flag parser match this ref; owned-string helpers come from the publication topic. This is not a historical app binary.",
+  "sources": {
+    "src/shared/terminal-kitty-keyboard-mode-tracker.ts": {
+      "baselineSha256": "2ee0bad47d4575046f71c16e0334a8ae8be531f0cfc67133abc287f8ae5aa403",
+      "fixedSha256": "a8da704564b9ab97aa344f380940021d3fa98f80af817751824d14271acb8a84",
+      "reverse": [
+        {
+          "from": "import { ownRetainedString } from './own-retained-string'\n",
+          "to": "",
+          "count": 1
+        },
+        { "from": "? ownRetainedString(tail) : ''", "to": "? tail : ''", "count": 1 }
+      ]
+    },
+    "src/main/daemon/terminal-mouse-mode-mirror.ts": {
+      "baselineSha256": "5bf8a94ad7ec3fdd151ba7559f49a229b2156818aba88f7b562bef258048acf1",
+      "fixedSha256": "e8f4888dabee5c4cc50b0f15584b3b1b5e2da4db1ba25695dd5762ef9c4a6fb3",
+      "reverse": [
+        {
+          "from": "import { ownRetainedString } from '../../shared/own-retained-string'\n",
+          "to": "",
+          "count": 1
+        },
+        { "from": "? ownRetainedString(tail) : ''", "to": "? tail : ''", "count": 2 }
+      ]
+    },
+    "src/shared/own-retained-string.ts": {
+      "baselineSha256": "addea88bc11c725192be2ff617b91315a875113844c95de03e5529cf3d7ef2e2",
+      "fixedSha256": "addea88bc11c725192be2ff617b91315a875113844c95de03e5529cf3d7ef2e2"
+    },
+    "src/shared/owned-utf16-suffix.ts": {
+      "baselineSha256": "1ca0bb35dfff2d9f3c02caee3d05b0e0c97378df71c878622acf703524d2c475",
+      "fixedSha256": "1ca0bb35dfff2d9f3c02caee3d05b0e0c97378df71c878622acf703524d2c475"
+    },
+    "src/shared/terminal-kitty-keyboard-flags.ts": {
+      "baselineSha256": "ee8ca63afdca8356fa12878e74973ff92d807aa8d99750b2415b42f4bccb0225",
+      "fixedSha256": "ee8ca63afdca8356fa12878e74973ff92d807aa8d99750b2415b42f4bccb0225"
+    }
+  }
+}
diff --git a/src/main/daemon/terminal-mouse-mode-mirror.ts b/src/main/daemon/terminal-mouse-mode-mirror.ts
index 8f8b284f7f4..7e2ea703cac 100644
--- a/src/main/daemon/terminal-mouse-mode-mirror.ts
+++ b/src/main/daemon/terminal-mouse-mode-mirror.ts
@@ -1,3 +1,4 @@
+import { ownRetainedString } from '../../shared/own-retained-string'
 import type { TerminalModes } from './types'
 
 type MouseTrackingMode = NonNullable<TerminalModes['mouseTrackingMode']>
@@ -105,10 +106,10 @@ export class TerminalMouseModeMirror {
       return tail
     }
     if (tail.startsWith('\x1b[?')) {
-      return this.isIncompleteParams(tail.slice(3)) ? tail : ''
+      return this.isIncompleteParams(tail.slice(3)) ? ownRetainedString(tail) : ''
     }
     if (tail.startsWith('\x9b?')) {
-      return this.isIncompleteParams(tail.slice(2)) ? tail : ''
+      return this.isIncompleteParams(tail.slice(2)) ? ownRetainedString(tail) : ''
     }
     return ''
   }
diff --git a/src/main/daemon/terminal-mouse-tail-retention.test.ts b/src/main/daemon/terminal-mouse-tail-retention.test.ts
new file mode 100644
index 00000000000..7a266b4b23d
--- /dev/null
+++ b/src/main/daemon/terminal-mouse-tail-retention.test.ts
@@ -0,0 +1,41 @@
+import { describe, expect, it } from 'vitest'
+import { TerminalMouseModeMirror } from './terminal-mouse-mode-mirror'
+
+function heapAfterGc(): number {
+  if (!('gc' in globalThis) || typeof globalThis.gc !== 'function') {
+    throw new Error('The test runner must enable --expose-gc')
+  }
+  // Isolate mirror ownership from V8's process-wide last successful regexp input.
+  void /reset/.test('reset')
+  globalThis.gc()
+  globalThis.gc()
+  return process.memoryUsage().heapUsed
+}
+
+describe('mouse mode scan tail retention', () => {
+  it.each(['\x1b[', '\x9b'])(
+    'retains a split %j mode sequence without retaining consumed output',
+    (introducer) => {
+      const before = heapAfterGc()
+      const mirrors = Array.from({ length: 8 }, (_value, index) => {
+        const mirror = new TerminalMouseModeMirror()
+        mirror.scan(`${index}:${'x'.repeat(4 * 1024 * 1024)}${introducer}?1049;2004;1000;`)
+        return mirror
+      })
+
+      expect(heapAfterGc() - before).toBeLessThan(2 * 1024 * 1024)
+      for (const mirror of mirrors) {
+        expect(mirror.mouseTrackingMode).toBe('none')
+        mirror.scan('1006h')
+        expect(mirror.mouseTrackingMode).toBe('vt200')
+        expect(mirror.sgrMouseMode).toBe(true)
+        mirror.scan('\x1b[?1016h')
+        expect(mirror.sgrMouseMode).toBe(false)
+        expect(mirror.sgrMousePixelsMode).toBe(true)
+        mirror.scan('\x1bc')
+        expect(mirror.mouseTrackingMode).toBe('none')
+        expect(mirror.sgrMousePixelsMode).toBe(false)
+      }
+    }
+  )
+})
diff --git a/src/shared/terminal-kitty-keyboard-mode-tracker.ts b/src/shared/terminal-kitty-keyboard-mode-tracker.ts
index cae87067973..72c9d5b91f3 100644
--- a/src/shared/terminal-kitty-keyboard-mode-tracker.ts
+++ b/src/shared/terminal-kitty-keyboard-mode-tracker.ts
@@ -1,3 +1,4 @@
+import { ownRetainedString } from './own-retained-string'
 import { parseTerminalKittyKeyboardFlags } from './terminal-kitty-keyboard-flags'
 
 // Why: PTY/SSH chunks can split an escape sequence before its final byte.
@@ -308,7 +309,7 @@ export class TerminalKittyKeyboardModeTracker {
     if (body === null) {
       return ''
     }
-    return this.isIncompleteSequenceBody(body) ? tail : ''
+    return this.isIncompleteSequenceBody(body) ? ownRetainedString(tail) : ''
   }
 
   private isIncompleteSequenceBody(body: string): boolean {
diff --git a/src/shared/terminal-kitty-keyboard-tail-retention.test.ts b/src/shared/terminal-kitty-keyboard-tail-retention.test.ts
new file mode 100644
index 00000000000..4c1b92acffd
--- /dev/null
+++ b/src/shared/terminal-kitty-keyboard-tail-retention.test.ts
@@ -0,0 +1,41 @@
+import { describe, expect, it } from 'vitest'
+import { TerminalKittyKeyboardModeTracker } from './terminal-kitty-keyboard-mode-tracker'
+
+const INCOMPLETE_MODE = '\x1b[?1049;2004;1000;'
+
+function heapAfterGc(): number {
+  if (!('gc' in globalThis) || typeof globalThis.gc !== 'function') {
+    throw new Error('The test runner must enable --expose-gc')
+  }
+  // Isolate tracker ownership from V8's process-wide last successful regexp input.
+  void /reset/.test('reset')
+  globalThis.gc()
+  globalThis.gc()
+  return process.memoryUsage().heapUsed
+}
+
+describe('kitty keyboard scan tail retention', () => {
+  it.each(['scan', 'scanReplay'] as const)(
+    '%s retains a split mode sequence without retaining consumed output',
+    (method) => {
+      const before = heapAfterGc()
+      const trackers = Array.from({ length: 8 }, (_value, index) => {
+        const tracker = new TerminalKittyKeyboardModeTracker()
+        tracker[method](`${index}:${'x'.repeat(4 * 1024 * 1024)}${INCOMPLETE_MODE}`)
+        return tracker
+      })
+
+      expect(heapAfterGc() - before).toBeLessThan(2 * 1024 * 1024)
+      for (const tracker of trackers) {
+        expect(tracker.isAlternateScreen).toBe(false)
+        tracker[method]('1006h\x1b[>3u')
+        expect(tracker.isAlternateScreen).toBe(true)
+        expect(tracker.flags).toBe(3)
+        tracker.scan('\x1b[<u')
+        expect(tracker.flags).toBe(0)
+        tracker.resetForSnapshot()
+        expect(tracker.snapshotFlags).toBeUndefined()
+      }
+    }
+  )
+})