Examine source code of NekoCap

{
  "manifest_version": 3,
  "name": "NekoCap",
  "description": "__MSG_extShortDescription__",
  "version": "1.23.2",
  "default_locale": "en",
  "action": {
    "default_icon": "icon16.png",
    "default_popup": "popup.html"
  },
  "background": {
    "scripts": [
      "js/background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "https://*.youtube.com/*",
        "https://*.tver.jp/*",
        "https://*.nicovideo.jp/*",
        "https://*.vimeo.com/*",
        "https://*.bilibili.com/*",
        "https://*.netflix.com/*",
        "https://*.primevideo.com/*",
        "https://*.twitter.com/*",
        "https://*.x.com/*",
        "https://*.wetv.vip/*",
        "https://*.tiktok.com/*",
        "https://*.iq.com/*",
        "https://*.abema.tv/*",
        "https://*.dailymotion.com/*",
        "https://*.bilibili.tv/*",
        "https://*.nogidoga.com/*",
        "https://*.cu.tbs.co.jp/*",
        "https://*.instagram.com/*",
        "https://*.unext.jp/*",
        "https://*.lemino.docomo.ne.jp/*",
        "https://*.oned.net/*",
        "https://*.archive.org/*"
      ],
      "all_frames": true,
      "run_at": "document_end",
      "js": [
        "js/content.js"
      ]
    },
    {
      "matches": [
        "https://*.youtube.com/*",
        "https://*.tver.jp/*",
        "https://*.nicovideo.jp/*",
        "https://*.vimeo.com/*",
        "https://*.bilibili.com/*",
        "https://*.netflix.com/*",
        "https://*.primevideo.com/*",
        "https://*.twitter.com/*",
        "https://*.x.com/*",
        "https://*.wetv.vip/*",
        "https://*.tiktok.com/*",
        "https://*.iq.com/*",
        "https://*.abema.tv/*",
        "https://*.dailymotion.com/*",
        "https://*.bilibili.tv/*",
        "https://*.nogidoga.com/*",
        "https://*.cu.tbs.co.jp/*",
        "https://*.instagram.com/*",
        "https://*.unext.jp/*",
        "https://*.lemino.docomo.ne.jp/*",
        "https://*.oned.net/*",
        "https://*.archive.org/*"
      ],
      "all_frames": true,
      "run_at": "document_start",
      "css": [
        "js/content.css"
      ]
    }
  ],
  "icons": {
    "16": "icon16.png",
    "48": "icon48.png",
    "128": "icon128.png"
  },
  "permissions": [
    "storage",
    "webNavigation",
    "identity"
  ],
  "web_accessible_resources": [
    {
      "resources": [
        "canvas-iframe.html",
        "canvas-iframe.js"
      ],
      "matches": [
        "https://*.youtube.com/*",
        "https://*.tver.jp/*",
        "https://*.nicovideo.jp/*",
        "https://*.vimeo.com/*",
        "https://*.bilibili.com/*",
        "https://*.netflix.com/*",
        "https://*.primevideo.com/*",
        "https://*.twitter.com/*",
        "https://*.x.com/*",
        "https://*.wetv.vip/*",
        "https://*.tiktok.com/*",
        "https://*.iq.com/*",
        "https://*.abema.tv/*",
        "https://*.dailymotion.com/*",
        "https://*.bilibili.tv/*",
        "https://*.nogidoga.com/*",
        "https://*.cu.tbs.co.jp/*",
        "https://*.instagram.com/*",
        "https://*.unext.jp/*",
        "https://*.lemino.docomo.ne.jp/*",
        "https://*.oned.net/*",
        "https://*.archive.org/*"
      ],
      "use_dynamic_url": true
    },
    {
      "resources": [
        "img/*.jpg",
        "img/*.png",
        "img/*.gif",
        "img/*.svg",
        "sub-assets/*.*",
        "js/subtitle-octopus/*.*"
      ],
      "matches": [
        "https://*.youtube.com/*",
        "https://*.tver.jp/*",
        "https://*.nicovideo.jp/*",
        "https://*.vimeo.com/*",
        "https://*.bilibili.com/*",
        "https://*.netflix.com/*",
        "https://*.primevideo.com/*",
        "https://*.twitter.com/*",
        "https://*.x.com/*",
        "https://*.wetv.vip/*",
        "https://*.tiktok.com/*",
        "https://*.iq.com/*",
        "https://*.abema.tv/*",
        "https://*.dailymotion.com/*",
        "https://*.bilibili.tv/*",
        "https://*.nogidoga.com/*",
        "https://*.cu.tbs.co.jp/*",
        "https://*.instagram.com/*",
        "https://*.unext.jp/*",
        "https://*.lemino.docomo.ne.jp/*",
        "https://*.oned.net/*",
        "https://*.archive.org/*"
      ]
    }
  ],
  "content_security_policy": {
    "extension_pages": "script-src 'self' *.google.com 'wasm-unsafe-eval'"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "nekocaption@gmail.com"
    }
  }
}