src-reducers-tabs.js.diff

diff --git a/src/reducers/tabs.js b/src/reducers/tabs.js
index c0fd22ea6..0c61e5b7e 100644
--- a/src/reducers/tabs.js
+++ b/src/reducers/tabs.js
@@ -12,7 +12,7 @@
 import { createSelector } from "reselect";
 import move from "lodash-move";
 
-import { prefs } from "../utils/prefs";
+import { prefs, asyncStore } from "../utils/prefs";
 import {
   getSource,
   getSources,
@@ -27,22 +27,24 @@ import type { SourcesState } from "./sources";
 type Tab = { url: string, framework?: string | null };
 export type TabList = Tab[];
 
-function update(state: TabList = prefs.tabs || [], action: Action): TabList {
+async function update(state: TabList = [], action: Action): TabList {
+  const currentTabs = await asyncStore.tabs;
+
   switch (action.type) {
     case "ADD_TAB":
     case "UPDATE_TAB":
-      return updateTabList(state, action);
+      updateTabList(currentTabs, action);
 
     case "MOVE_TAB":
-      return moveTabInList(state, action);
+      moveTabInList(currentTabs, action);
 
     case "CLOSE_TAB":
     case "CLOSE_TABS":
-      prefs.tabs = action.tabs;
-      return action.tabs;
+      // prefs.tabs = action.tabs;
+      asyncStore.tabs = action.tabs;
 
     default:
-      return state;
+    // return state;
   }
 }
 

src-utils-prefs.js.diff

diff --git a/src/utils/prefs.js b/src/utils/prefs.js
index e30a00fa2..ee2e16ea6 100644
--- a/src/utils/prefs.js
+++ b/src/utils/prefs.js
@@ -114,12 +114,14 @@ export const features = new PrefsHelper("devtools.debugger.features", {
 });
 
 export const asyncStore = asyncStoreHelper("debugger", {
-  pendingBreakpoints: ["pending-breakpoints", {}]
+  pendingBreakpoints: ["pending-breakpoints", {}],
+  tabs: ["tabs", []]
 });
 
 if (prefs.debuggerPrefsSchemaVersion !== prefsSchemaVersion) {
   // clear pending Breakpoints
   prefs.pendingBreakpoints = {};
   prefs.tabs = [];
+  asyncStore.tabs = []; // Hmm, not sure if we need this
   prefs.debuggerPrefsSchemaVersion = prefsSchemaVersion;
 }