From 20e1144c3b9e828bed3bb1d54ce178b5f043ae82 Mon Sep 17 00:00:00 2001
From: Yury Semikhatsky <yurys@chromium.org>
Date: Tue, 5 Aug 2025 14:18:04 -0700
Subject: [PATCH] chore(extension): proper watchdog for inactive page selector
 (#835)

---
 extension/src/background.ts | 44 +++++++++++++++++++------------------
 extension/tsconfig.json     |  1 +
 2 files changed, 24 insertions(+), 21 deletions(-)

diff --git a/extension/src/background.ts b/extension/src/background.ts
index 41b4399..e7b2efe 100644
--- a/extension/src/background.ts
+++ b/extension/src/background.ts
@@ -36,6 +36,7 @@ class TabShareExtension {
   constructor() {
     chrome.tabs.onRemoved.addListener(this._onTabRemoved.bind(this));
     chrome.tabs.onUpdated.addListener(this._onTabUpdated.bind(this));
+    chrome.tabs.onActivated.addListener(this._onTabActivated.bind(this));
     chrome.runtime.onMessage.addListener(this._onMessage.bind(this));
   }
 
@@ -153,30 +154,31 @@ class TabShareExtension {
     this._connectedTabId = null;
   }
 
-  private async _onTabUpdated(tabId: number, changeInfo: chrome.tabs.TabChangeInfo, tab: chrome.tabs.Tab): Promise<void> {
-    if (changeInfo.status === 'complete' && this._connectedTabId === tabId) {
-      await this._setConnectedTabId(tabId);
-      return;
-    }
-    const pending = this._pendingTabSelection.get(tabId);
-    if (!pending)
-      return;
-    if (tab.active && pending.timerId) {
-      clearTimeout(pending.timerId);
-      pending.timerId = undefined;
-      return;
-    }
-    if (!tab.active && !pending.timerId) {
-      debugLog('Starting inactivity timer', tabId);
-      pending.timerId = window.setTimeout(() => {
-        const existed = this._pendingTabSelection.delete(tabId);
-        if (existed)
-          pending.connection.close('Tab is not active');
-      }, 5000);
-      return;
+  private _onTabActivated(activeInfo: chrome.tabs.TabActiveInfo) {
+    for (const [tabId, pending] of this._pendingTabSelection) {
+      if (tabId === activeInfo.tabId) {
+        if (pending.timerId) {
+          clearTimeout(pending.timerId);
+          pending.timerId = undefined;
+        }
+        continue;
+      }
+      if (!pending.timerId) {
+        pending.timerId = setTimeout(() => {
+          const existed = this._pendingTabSelection.delete(tabId);
+          if (existed)
+            pending.connection.close('Tab has been inactive for 5 seconds');
+        }, 5000);
+        return;
+      }
     }
   }
 
+  private _onTabUpdated(tabId: number, changeInfo: chrome.tabs.TabChangeInfo, tab: chrome.tabs.Tab) {
+    if (changeInfo.status === 'complete' && this._connectedTabId === tabId)
+      void this._setConnectedTabId(tabId);
+  }
+
   private async _getTabs(): Promise<chrome.tabs.Tab[]> {
     const tabs = await chrome.tabs.query({});
     return tabs.filter(tab => tab.url && !['chrome:', 'edge:', 'devtools:'].some(scheme => tab.url!.startsWith(scheme)));
diff --git a/extension/tsconfig.json b/extension/tsconfig.json
index 6fa7759..70fb340 100644
--- a/extension/tsconfig.json
+++ b/extension/tsconfig.json
@@ -8,6 +8,7 @@
     "rootDir": "src",
     "outDir": "./dist/lib",
     "resolveJsonModule": true,
+    "types": ["chrome"],
     "jsx": "react-jsx",
     "jsxImportSource": "react"
   },