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diff --git a/packages/web-util/src/hooks/useLocalStorage.ts b/packages/web-util/src/hooks/useLocalStorage.ts
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+++ b/packages/web-util/src/hooks/useLocalStorage.ts
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+/*
+ This file is part of GNU Anastasis
+ (C) 2021-2022 Anastasis SARL
+
+ GNU Anastasis is free software; you can redistribute it and/or modify it under the
+ terms of the GNU Affero General Public License as published by the Free Software
+ Foundation; either version 3, or (at your option) any later version.
+
+ GNU Anastasis is distributed in the hope that it will be useful, but WITHOUT ANY
+ WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+ A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more details.
+
+ You should have received a copy of the GNU Affero General Public License along with
+ GNU Anastasis; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
+ */
+
+/**
+ *
+ * @author Sebastian Javier Marchano (sebasjm)
+ */
+
+import { AbsoluteTime, Codec, codecForString } from "@gnu-taler/taler-util";
+import { useEffect, useState } from "preact/hooks";
+import {
+  ObservableMap,
+  browserStorageMap,
+  localStorageMap,
+  memoryMap,
+} from "../utils/observable.js";
+
+declare const opaque_StorageKey: unique symbol;
+
+export type StorageKey<Key> = {
+  id: string;
+  [opaque_StorageKey]: true;
+  codec: Codec<Key>;
+};
+
+export function buildStorageKey<Key>(
+  name: string,
+  codec: Codec<Key>,
+): StorageKey<Key>;
+export function buildStorageKey(name: string): StorageKey<string>;
+export function buildStorageKey<Key = string>(
+  name: string,
+  codec?: Codec<Key>,
+): StorageKey<Key> {
+  return {
+    id: name,
+    codec: codec ?? (codecForString() as Codec<Key>),
+  } as StorageKey<Key>;
+}
+
+export interface StorageState<Type = string> {
+  value?: Type;
+  update: (s: Type) => void;
+  reset: () => void;
+}
+
+const supportLocalStorage = typeof window !== "undefined";
+const supportBrowserStorage =
+  typeof chrome !== "undefined" && typeof chrome.storage !== "undefined";
+
+/**
+ * Build setting storage
+ */
+const storage: ObservableMap<string, string> = (function buildStorage() {
+  if (supportBrowserStorage) {
+    //browser storage is like local storage but
+    //with app sync.
+    //Works for almost every browser
+    if (supportLocalStorage) {
+      return browserStorageMap(localStorageMap());
+    } else {
+      // service worker doesn't have local storage
+      return browserStorageMap(memoryMap<string>());
+    }
+  } else if (supportLocalStorage) {
+    // fallback if browser is too old
+    return localStorageMap();
+  } else {
+    // new need to save settings somewhere
+    return memoryMap<string>();
+  }
+})();
+//with initial value
+export function useLocalStorage<Type = string>(
+  key: StorageKey<Type>,
+  defaultValue: Type,
+): Required<StorageState<Type>>;
+//without initial value
+export function useLocalStorage<Type = string>(
+  key: StorageKey<Type>,
+): StorageState<Type>;
+// impl
+export function useLocalStorage<Type = string>(
+  key: StorageKey<Type>,
+  defaultValue?: Type,
+): StorageState<Type> {
+  const current = convert(storage.get(key.id), key, defaultValue);
+
+  const [_, setStoredValue] = useState(AbsoluteTime.now().t_ms);
+
+  useEffect(() => {
+    return storage.onUpdate(key.id, () => {
+      // const newValue = storage.get(key.id);
+      setStoredValue(AbsoluteTime.now().t_ms);
+    });
+  }, [key.id]);
+
+  const setValue = (value?: Type): void => {
+    if (value === undefined) {
+      storage.delete(key.id);
+    } else {
+      storage.set(
+        key.id,
+        key.codec ? JSON.stringify(value) : (value as string),
+      );
+    }
+  };
+
+  return {
+    value: current,
+    update: setValue,
+    reset: () => {
+      setValue(defaultValue);
+    },
+  };
+}
+
+function convert<Type>(updated: string | undefined, key: StorageKey<Type>, defaultValue?: Type): Type | undefined {
+  if (updated === undefined) return defaultValue; //optional
+  try {
+    return key.codec.decode(JSON.parse(updated));
+  } catch (e) {
+    //decode error
+    return defaultValue;
+  }
+}