Examine source code of PantallaFacil

{
  "manifest_version": 2,
  "name": "PantallaFacil Extension 2019.01.01",
  "description": "Reproductor de anuncios de PantallaFácil, extensión para Firefox. Más información en https://PantallaFacil.TV",
  "version": "2019.1.1",
  "background": {
    "scripts": [
      "url.js"
    ]
  },
  "browser_action": {
    "browser_style": true,
    "default_icon": {
      "48": "/logo.png",
      "128": "/logo.png"
    }
  }
}