From 9be198011daa2baebca8cb922abe4fe57e0074e2 Mon Sep 17 00:00:00 2001
From: "prompt.ac/@jeffrey" <mail@aesthetic.computer>
Date: Thu, 17 Sep 2026 18:47:23 -0700
Subject: [PATCH] Add opt-in single-window gate to Captutor Stage

---
 slab/captutor/lib/single-tab.mjs       | 8 +++++---
 slab/captutor/test/single-tab.test.mjs | 3 +++
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/slab/captutor/lib/single-tab.mjs b/slab/captutor/lib/single-tab.mjs
index 5d8cf042d7..563cad856a 100644
--- a/slab/captutor/lib/single-tab.mjs
+++ b/slab/captutor/lib/single-tab.mjs
@@ -1,14 +1,16 @@
 // Read-only recording gate: never close or navigate unrelated tabs.
-export async function assertSingleRecordingTab(cdp){
+export async function assertSingleRecordingTab(cdp,{singleWindow=false}={}){
  const current=await cdp.send('Browser.getWindowForTarget');
  const {targetInfos}=await cdp.send('Target.getTargets');
  if(!Array.isArray(targetInfos))throw Error('Cannot inspect recording-window tabs');
- let count=0;
+ let count=0;const windows=new Set();
  for(const t of targetInfos){
   if(t.type!=='page')continue;
   const {windowId}=await cdp.send('Browser.getWindowForTarget',{targetId:t.targetId});
+  windows.add(windowId);
   if(windowId===current.windowId)count++;
  }
  if(count!==1)throw Error(`Recording window has ${count} tabs; move the project tab into its own window before recording. Preserve all other tabs.`);
- return {windowId:current.windowId,tabCount:count};
+ if(singleWindow&&windows.size!==1)throw Error(`Stage sees ${windows.size} Chrome windows; close completed mission verification/preview windows before recording. Preserve unrelated work and pause capture if it cannot be isolated.`);
+ return {windowId:current.windowId,tabCount:count,windowCount:windows.size};
 }
diff --git a/slab/captutor/test/single-tab.test.mjs b/slab/captutor/test/single-tab.test.mjs
index 43547194ff..a91fc3b2de 100644
--- a/slab/captutor/test/single-tab.test.mjs
+++ b/slab/captutor/test/single-tab.test.mjs
@@ -3,3 +3,6 @@ const mock=windows=>({send:async(method,p)=>{if(method==='Target.getTargets')ret
 test('one recording tab accepts other windows without mutation',async()=>assert.equal((await assertSingleRecordingTab(mock([1,2,2]))).tabCount,1));
 test('extra recording tab fails without closing it',async()=>assert.rejects(assertSingleRecordingTab(mock([1,1])),/2 tabs/));
 test('missing recording target fails closed',async()=>assert.rejects(assertSingleRecordingTab(mock([2])),/0 tabs/));
+
+test('Stage rejects a second window without closing it',async()=>assert.rejects(assertSingleRecordingTab(mock([1,2]),{singleWindow:true}),/2 Chrome windows/));
+test('Stage accepts exactly one window and tab',async()=>assert.equal((await assertSingleRecordingTab(mock([1]),{singleWindow:true})).windowCount,1));
-- 
2.51.2