fix(desktop): keep deferred popups in their opener's session

- A background-tab popup with no Chromium-supplied contents now opens in the opener's session rather than the agent partition
- Driver tests expect the referrer options loadURL now receives

Author: waleedlatif1

apps/desktop/src/main/browser-agent/driver.test.ts

@@ -804,7 +804,7 @@ describe('executeTool', () => {
     const popup = session.activeTab()?.view.webContents
     if (!popup) throw new Error('Expected user popup tab')
     expect(session.automationTab()?.view.webContents).toBe(source)
-    expect(popup.loadURL).toHaveBeenCalledWith('https://user-popup.example/')
+    expect(popup.loadURL).toHaveBeenCalledWith('https://user-popup.example/', expect.anything())
   })
 
   it('keeps agent-opened target-blank tabs agent-owned after dispatch ends', async () => {
@@ -823,7 +823,7 @@ describe('executeTool', () => {
     expect(session.activeTab()?.view.webContents).toBe(source)
     session.setAutomationActive(false)
     expect(session.automationTab()?.view.webContents).toBe(popup)
-    expect(popup.loadURL).toHaveBeenCalledWith('https://agent-popup.example/')
+    expect(popup.loadURL).toHaveBeenCalledWith('https://agent-popup.example/', expect.anything())
   })
 
   it('does not report a timed-out restored tab as ready to the model', async () => {

apps/desktop/src/main/browser-agent/session.test.ts

@@ -32,7 +32,7 @@ function _setPlatform(platform: NodeJS.Platform): void {
   Object.defineProperty(process, 'platform', { configurable: true, value: platform })
 }
 
-type PopupHandler = (details: { url: string }) => {
+type PopupHandler = (details: { url: string; disposition?: string }) => {
   action: string
   outlivesOpener?: boolean
   createWindow?: (options: Record<string, unknown>) => unknown
@@ -2321,13 +2321,28 @@ describe('importAgentCookies', () => {
 
 describe('first-party browser sessions', () => {
   const origin = 'https://www.dev.sim.ai'
+  const appSession = new WebContentsView().webContents.session
   function initialize(persistence?: sessionModule.BrowserSessionPersistence) {
     return freshSession(null, {}, persistence, undefined, {
       origin,
-      session: new WebContentsView().webContents.session,
+      session: appSession,
     })
   }
 
+  it("opens a deferred blank popup in its opener's session", () => {
+    const session = initialize()
+    const opener = session.addAutomationTab(`${origin}/home`).view.webContents
+    Object.assign(opener, { session: appSession })
+    const openWindow = vi.mocked(opener.setWindowOpenHandler).mock.calls[0]?.[0] as PopupHandler
+
+    const popup = openWindow({ url: 'about:blank', disposition: 'background-tab' }).createWindow?.(
+      {}
+    ) as WebContents
+    expect(popup).not.toBe(opener)
+    expect(agentAppOrigin(popup)).toBe(origin)
+    expect(popup.loadURL).not.toHaveBeenCalled()
+  })
+
   it('keeps a populated tab and its history when crossing the session boundary', () => {
     const session = initialize()
     const tab = session.addAutomationTab(`${origin}/home`)

apps/desktop/src/main/browser-agent/session.ts

@@ -2318,7 +2318,7 @@ function adoptPopupTab(
   }: { agentOwned: boolean; background: boolean; referrer?: Referrer }
 ): WebContents {
   const openerTabId = tabForContents(opener)?.id
-  const tab = openLinkTab(url, { agentOwned, background }, popup)
+  const tab = openLinkTab(url, { agentOwned, background }, { opener, options: popup })
   tab.openerTabId = openerTabId
   tab.returnToOpenerOnClose = true
   const contents = tab.view.webContents
@@ -2336,7 +2336,7 @@ function adoptPopupTab(
 function openLinkTab(
   url: string,
   { agentOwned, background }: { agentOwned: boolean; background: boolean },
-  popup?: PopupWindowOptions
+  popup?: AdoptedPopup
 ): AgentTab {
   if (agentOwned) return addAutomationTab(url, popup)
   if (background) {
@@ -2379,23 +2379,33 @@ function openTabWithUrl(
  */
 type PopupWindowOptions = BrowserWindowConstructorOptions & WebContentsViewConstructorOptions
 
+/** A page-opened window becoming a tab, with the page that opened it. */
+interface AdoptedPopup {
+  opener: WebContents
+  options: PopupWindowOptions
+}
+
 /**
  * Creates a tab's view. `popup` adopts a page-opened window's WebContents, which Chromium created
  * with the opener's (identical) web preferences, so the opener relationship and its session stay
- * intact; callers only adopt popups that are blank or whose URL belongs to the opener's session.
+ * intact; a deferred popup without one gets a fresh view in the opener's session. Callers only
+ * adopt popups that are blank or whose URL belongs to the opener's session.
  */
-function createTabView(url?: string, popup?: PopupWindowOptions): WebContentsView {
+function createTabView(url?: string, popup?: AdoptedPopup): WebContentsView {
   let appSession: BrowserAppSession | undefined
-  if (popup?.webContents) {
-    // A blank popup's URL names no origin, so trust the session Chromium created it in.
-    if (browserAppSession && popup.webContents.session === browserAppSession.session) {
+  if (popup) {
+    // A popup follows its opener's session (Chromium creates it there); a blank URL names no origin.
+    const popupSession = popup.options.webContents?.session ?? popup.opener.session
+    if (browserAppSession && popupSession === browserAppSession.session) {
       appSession = browserAppSession
     }
   } else if (url && browserAppSession && isAppOrigin(url, browserAppSession.origin)) {
     appSession = browserAppSession
   }
   const scopeId = getBrowserScopeId()
-  const view = popup?.webContents ? new WebContentsView(popup) : createFreshTabView(appSession)
+  const view = popup?.options.webContents
+    ? new WebContentsView(popup.options)
+    : createFreshTabView(appSession)
   try {
     /** Detached tabs must lay out before a foreground panel owns their native view. */
     const [width, height] = getMainWindow()?.getContentSize() ?? [1280, 720]
@@ -2960,7 +2970,7 @@ interface AddTabOptions {
   activate?: boolean
   notify?: boolean
   url?: string
-  popup?: PopupWindowOptions
+  popup?: AdoptedPopup
 }
 
 function addTabInternal({
@@ -3441,7 +3451,7 @@ export function restoreBrowserSession(): void {
   }
 }
 
-export function addTab(url?: string, popup?: PopupWindowOptions): AgentTab {
+export function addTab(url?: string, popup?: AdoptedPopup): AgentTab {
   restoreBrowserSession()
   currentScope.visibleTabUserSelected = true
   return addTabInternal({ url, popup })
@@ -3452,7 +3462,7 @@ export function addTab(url?: string, popup?: PopupWindowOptions): AgentTab {
  * renderer's decision: every page is a resource tab there, and it shows the
  * agent's tab or badges it depending on what the user is doing.
  */
-export function addAutomationTab(url?: string, popup?: PopupWindowOptions): AgentTab {
+export function addAutomationTab(url?: string, popup?: AdoptedPopup): AgentTab {
   restoreBrowserSession()
   const tab = addTabInternal({ activate: false, notify: false, url, popup })
   currentScope.automationTabId = tab.id