Please address the comments from this code review:
## Overall Comments
- You’re using `isFirefox` in popup.js without declaring it there—add a Firefox detection (e.g. `const isFirefox = /Firefox/.test(navigator.userAgent)`) at the top of popup.js so the date‐input workaround actually runs.
- The change to manifest.json removes the Chrome `background.service_worker` section—ensure you conditionally include or maintain the service worker entry so Chrome extensions still load the background script correctly.
- Consider extracting repeated `browser.storage.local.get/set` calls into a small helper so you don’t have to manually swap `chrome`/`browser` in every method and reduce duplication.

## Individual Comments

### Comment 1
<location> `src/scripts/popup.js:47` </location>
<code_context>

 document.addEventListener('DOMContentLoaded', function() {
+    // Firefox date input fix
+    if (isFirefox) {
+        document.querySelectorAll('input[type="date"]').forEach(input => {
+            if (!input.value) {
</code_context>

<issue_to_address>
Undefined isFirefox in popup.js

`isFirefox` must be defined or imported before use to avoid a ReferenceError.
</issue_to_address>

### Comment 2
<location> `src/scripts/browser-polyfill.js:2` </location>
<code_context>
+// scripts/browser-polyfill.js
+if (typeof browser === "undefined") {
+    window.browser = typeof chrome !== "undefined" ? chrome : {};
+}
</code_context>

<issue_to_address>
Polyfill doesn't override native browser API in Firefox

Firefox's native `browser` object uses promises, but your code expects callbacks. To ensure consistent behavior across browsers, use Mozilla's webextension-polyfill.

Suggested implementation:

```javascript
import browser from 'webextension-polyfill';
window.browser = browser;

```

1. Make sure to install the `webextension-polyfill` package in your project:
   ```
   npm install webextension-polyfill
   ```
2. If your build system does not support ES modules or import syntax in this context, you may need to use a CDN or require statement, or adjust your bundler configuration.
3. Ensure this polyfill is loaded before any other scripts that use the `browser` API.
</issue_to_address>

Please address the comments from this code review:
## Overall Comments
- Extract the repeated browser.storage.local.get/set logic into a small helper module to reduce duplication and simplify maintenance.
- Rename `getbrowserData` to `getBrowserData` (or another consistent camelCase) to match the rest of your function naming conventions.
- Make sure `browser-polyfill.js` is loaded before any other scripts (in both popup.html and content scripts) so that the `browser` namespace is always available.

## Individual Comments

### Comment 1
<location> `src/scripts/browser-polyfill.js:2` </location>
<code_context>
+// scripts/browser-polyfill.js
+if (typeof browser === "undefined") {
+    window.browser = typeof chrome !== "undefined" ? chrome : {};
+}
</code_context>

<issue_to_address>
Polyfill only aliases browser to chrome without promise conversion

This approach does not provide promise-based API support. Using `webextension-polyfill` would ensure consistent promise support across browsers.

Suggested implementation:

```javascript
/**
 * scripts/browser-polyfill.js
 * Use the official webextension-polyfill to provide a consistent, promise-based browser API.
 * See: https://github.com/mozilla/webextension-polyfill
 */

// Import the polyfill if not already present
// You must install webextension-polyfill as a dependency: npm install webextension-polyfill

import browser from 'webextension-polyfill';

if (typeof window !== "undefined") {
    window.browser = browser;
}

```

- Ensure that `webextension-polyfill` is installed in your project (`npm install webextension-polyfill`).
- If your build system does not support ES modules or import syntax in this context, you may need to use a different approach to include the polyfill, such as referencing the CDN version or using a bundler.
</issue_to_address>