Fixed #133

Author: mantou132

Diff for: .eslintrc.js

@@ -12,6 +12,7 @@ module.exports = {
     sourceType: 'module',
   },
   rules: {
+    'no-fallthrough': 2,
     // https://github.com/benmosher/eslint-plugin-import/blob/HEAD/docs/rules/order.md
     'import/order': [
       'error',

Diff for: src/background.ts

@@ -68,6 +68,7 @@ browser.runtime.onMessage.addListener(async (msg: Message, sender) => {
         type: Event.SEND_OPTIONS,
         data: { ...options, i18nMap },
       });
+      return;
     }
     case Event.POPUP_ACTIVE: {
       if (data === true) {