use message broadcast in mv2

src/background/broadcast.js

@@ -2,11 +2,13 @@ import '@/js/browser';
 import {kBroadcast} from '@/js/consts';
 import {rxIgnorableError} from '@/js/msg-api';
 import {chromeLocal, chromeSession} from '@/js/storage-util';
+import {ownRoot} from '@/js/urls';
+import {getWindowClients} from './util';
 
 let toBroadcast;
 
 export function broadcast(data) {
-  toBroadcast ??= (setTimeout(doBroadcast), []);
+  toBroadcast ??= (setTimeout(__.MV3 ? doBroadcast : doBroadcastMV2), []);
   toBroadcast.push(data);
 }
 
@@ -16,6 +18,25 @@ function doBroadcast() {
   toBroadcast = null;
 }
 
+async function doBroadcastMV2() {
+  const jobs = [];
+  const [clients, tabs] = await Promise.all([
+    __.MV3 && getWindowClients(), // TODO: detect the popup in Chrome MV2 incognito window?
+    browser.tabs.query({}),
+  ]);
+  const iActive = tabs.find(t => t.active);
+  const data = toBroadcast;
+  toBroadcast = null;
+  if (iActive > 0)
+    tabs.unshift(tabs.splice(iActive, 1)[0]);
+  if (!__.MV3 || clients[0])
+    jobs.push(broadcastExtension(data, true));
+  for (const {url, id} of tabs)
+    if (url && !url.startsWith(ownRoot) && jobs.push(sendTab(id, data, null, true)) > 20)
+      await Promise.all(jobs.splice(0));
+  await Promise.all(jobs);
+}
+
 export function broadcastExtension(data, multi) {
   return unwrap(browser.runtime.sendMessage({data, multi}));
 }

src/js/msg.js

@@ -26,9 +26,8 @@ if (__.ENTRY) {
     if (fnOff) port.onDisconnect.addListener(fnOff);
   });
 }
-if (!__.IS_BG) {
-  const S = chrome.storage;
-  (S.session || !__.MV3 && (S.local.onChanged ? S.local : S)).onChanged.addListener(onStorage);
+if (__.MV3 && !__.IS_BG) {
+  chrome.storage.session.onChanged.addListener(onStorage);
 }
 
 export function _execute(data, sender, multi) {