diff --git a/src/main/runtime/orca-runtime-capture-provider-terminal-buffer.ts b/src/main/runtime/orca-runtime-capture-provider-terminal-buffer.ts
index acf4f60532..fc9ba31964 100644
--- a/src/main/runtime/orca-runtime-capture-provider-terminal-buffer.ts
+++ b/src/main/runtime/orca-runtime-capture-provider-terminal-buffer.ts
@@ -31,7 +31,7 @@ export class OrcaRuntimeWithCaptureProviderTerminalBuffer extends OrcaRuntimeWit
       // Why: daemon PTYs survive an app relaunch before any renderer mounts.
       // Mobile still needs their retained history without navigating desktop.
       const snapshot = await this.ptyController?.serializeProviderBuffer?.(ptyId, opts)
-      if (!snapshot || this.getPtyLifecycleGeneration(ptyId) !== generation) {
+      if (!snapshot || this.ptyLifecycleGenerationById.get(ptyId) !== generation) {
         return null
       }
       const snapshotModeTracker = new TerminalKittyKeyboardModeTracker()
@@ -73,7 +73,10 @@ export class OrcaRuntimeWithCaptureProviderTerminalBuffer extends OrcaRuntimeWit
       return null
     } finally {
       liveModeTrackers.delete(liveModeTracker)
-      if (liveModeTrackers.size === 0) {
+      if (
+        liveModeTrackers.size === 0 &&
+        this.providerModeSnapshotScansByPtyId.get(ptyId) === liveModeTrackers
+      ) {
         this.providerModeSnapshotScansByPtyId.delete(ptyId)
       }
     }
@@ -163,7 +166,7 @@ export class OrcaRuntimeWithCaptureProviderTerminalBuffer extends OrcaRuntimeWit
     if (snapshotOptions.visibleScreenOnly) {
       const projection = await this.parseVisibleSnapshot(snapshot)
       // Live bytes ordered after the provider frame make that frame stale.
-      return this.getPtyLifecycleGeneration(ptyId) === generation &&
+      return this.ptyLifecycleGenerationById.get(ptyId) === generation &&
         this.getPtyOutputSequence(ptyId) <= snapshot.seq
         ? projection
         : { lines: [] }
@@ -180,7 +183,7 @@ export class OrcaRuntimeWithCaptureProviderTerminalBuffer extends OrcaRuntimeWit
     try {
       await emulator.write(data)
       const projection = projectTerminalTailLines(emulator, lineLimit)
-      return this.getPtyLifecycleGeneration(ptyId) === generation &&
+      return this.ptyLifecycleGenerationById.get(ptyId) === generation &&
         this.getPtyOutputSequence(ptyId) <= snapshot.seq
         ? projection
         : { lines: [] }
diff --git a/src/main/runtime/orca-runtime-create-pty-headless-terminal-state.ts b/src/main/runtime/orca-runtime-create-pty-headless-terminal-state.ts
index da5d824ef6..b9f3547850 100644
--- a/src/main/runtime/orca-runtime-create-pty-headless-terminal-state.ts
+++ b/src/main/runtime/orca-runtime-create-pty-headless-terminal-state.ts
@@ -112,8 +112,11 @@ export class OrcaRuntimeWithCreatePtyHeadlessTerminalState extends OrcaRuntimeWi
     this.headlessTerminals.set(ptyId, state)
     state.writeChain = state.writeChain
       .then(async () => {
+        if (this.headlessTerminals.get(ptyId) !== state) {
+          return
+        }
         const snapshot = await this.serializeProviderTerminalBuffer(ptyId)
-        if (!snapshot) {
+        if (this.headlessTerminals.get(ptyId) !== state || !snapshot) {
           return
         }
         const data = `${snapshot.scrollbackAnsi ?? ''}${snapshot.data}`
@@ -123,6 +126,9 @@ export class OrcaRuntimeWithCreatePtyHeadlessTerminalState extends OrcaRuntimeWi
           this.recordOsc7MetadataForPty(ptyId, data)
         }
         await state.emulator.write(data)
+        if (this.headlessTerminals.get(ptyId) !== state) {
+          return
+        }
         if (snapshot.cwd !== undefined) {
           state.emulator.setCwd(snapshot.cwd)
           if (!this.terminalCwdByPtyId.has(ptyId) && snapshot.cwd?.trim()) {
@@ -141,7 +147,9 @@ export class OrcaRuntimeWithCreatePtyHeadlessTerminalState extends OrcaRuntimeWi
         // Best-effort: live bytes already chain behind this replacement state.
       })
       .finally(() => {
-        this.providerSnapshotPreferredPtys.delete(ptyId)
+        if (this.headlessTerminals.get(ptyId) === state) {
+          this.providerSnapshotPreferredPtys.delete(ptyId)
+        }
       })
   }
 
diff --git a/src/main/runtime/orca-runtime-maybe-hydrate-headless-from-renderer.ts b/src/main/runtime/orca-runtime-maybe-hydrate-headless-from-renderer.ts
index 163ffaecdb..63135f261b 100644
--- a/src/main/runtime/orca-runtime-maybe-hydrate-headless-from-renderer.ts
+++ b/src/main/runtime/orca-runtime-maybe-hydrate-headless-from-renderer.ts
@@ -51,6 +51,9 @@ export class OrcaRuntimeWithMaybeHydrateHeadlessFromRenderer extends OrcaRuntime
     // setting headlessTerminals, the live byte would lazy-create a separate
     // state and the seed-resolve would overwrite it, dropping live bytes.
     state.writeChain = state.writeChain.then(async () => {
+      if (this.headlessTerminals.get(ptyId) !== state) {
+        return
+      }
       try {
         // Why the scrollback is not suppressed mid-TUI: the seed IS the model's
         // normal buffer, so zeroing it while an alt-screen agent was up left the
@@ -58,7 +61,11 @@ export class OrcaRuntimeWithMaybeHydrateHeadlessFromRenderer extends OrcaRuntime
         const rendered = await controller.serializeBuffer!(ptyId, {
           scrollbackRows: MOBILE_SUBSCRIBE_SCROLLBACK_ROWS
         })
-        if (!rendered || rendered.data.length === 0) {
+        if (
+          this.headlessTerminals.get(ptyId) !== state ||
+          !rendered ||
+          rendered.data.length === 0
+        ) {
           return
         }
         this.recordOsc7MetadataForPty(ptyId, rendered.data)
@@ -70,6 +77,9 @@ export class OrcaRuntimeWithMaybeHydrateHeadlessFromRenderer extends OrcaRuntime
           state.emulator.resize(rendered.cols, rendered.rows)
         }
         await state.emulator.write(rendered.data)
+        if (this.headlessTerminals.get(ptyId) !== state) {
+          return
+        }
         const ptyDims = this.getTerminalSize(ptyId)
         if (ptyDims && (ptyDims.cols !== rendered.cols || ptyDims.rows !== rendered.rows)) {
           state.emulator.resize(ptyDims.cols, ptyDims.rows)
@@ -91,7 +101,9 @@ export class OrcaRuntimeWithMaybeHydrateHeadlessFromRenderer extends OrcaRuntime
         // Hydration is best-effort. Live writes continue via the same
         // writeChain that this catch-arm leaves intact.
       } finally {
-        this.headlessHydrationState.set(ptyId, 'done')
+        if (this.headlessTerminals.get(ptyId) === state) {
+          this.headlessHydrationState.set(ptyId, 'done')
+        }
       }
     })
   }
diff --git a/src/main/runtime/orca-runtime-serialize-main-terminal-buffer.ts b/src/main/runtime/orca-runtime-serialize-main-terminal-buffer.ts
index 6559dbfd34..5b6da61d14 100644
--- a/src/main/runtime/orca-runtime-serialize-main-terminal-buffer.ts
+++ b/src/main/runtime/orca-runtime-serialize-main-terminal-buffer.ts
@@ -134,15 +134,24 @@ export class OrcaRuntimeWithSerializeMainTerminalBuffer extends OrcaRuntimeWithA
     this.recordRecentPtyOutputForPathProvenance(ptyId, data)
     state.writeChain = state.writeChain
       .then(async () => {
+        if (this.headlessTerminals.get(ptyId) !== state) {
+          return
+        }
         // Why: seed writes never set forwardQueryReplies — the main-side
         // replay guard. A snapshot containing old queries must answer no one.
         await state.emulator.write(data)
+        if (this.headlessTerminals.get(ptyId) !== state) {
+          return
+        }
         // Why AFTER the seed write: the snapshot payload cannot carry kitty
         // pushes (rehydrateSequences deliberately omits them), but ordering
         // behind it keeps the parse deterministic. Unflagged like the seed —
         // re-applying flags must answer no one.
         if (typeof metadata.kittyKeyboardFlags === 'number') {
           await state.emulator.applyKittyKeyboardFlags(metadata.kittyKeyboardFlags)
+          if (this.headlessTerminals.get(ptyId) !== state) {
+            return
+          }
         }
         if (metadata.cwd !== undefined) {
           state.emulator.setCwd(metadata.cwd)