manifest.json

{
  "name": "Spotify Controls",
  "version": "0.0.0.2",
  "description": "Extension to control Spotify player on Extension tab",
  "permissions": ["storage", "tabs"],
  "minimum_chrome_version": "55",
  "content_scripts": [
	   {
		 "matches": ["https://open.spotify.com/*"],
		 "js": ["contentScript.js"]
	   }
  ],
  "commands": {
      "spotify-pause-key": {
        "suggested_key": {
          "default": "Ctrl+Shift+2"
        },
        "description": "Spotify stop command",
        "global": true
      },
      "spotify-resume-key": {
        "suggested_key": {
          "default": "Ctrl+Shift+3"
        },
        "description": "Spotify resume command",
        "global": true
      },
	  "spotify-forward-key": {
        "suggested_key": {
          "default": "Ctrl+Shift+4"
        },
        "description": "Spotify forward command",
        "global": true
      }
  },
  "browser_action": {
	  "default_icon": {                   
		  "16": "images/silence16.png",
		  "32": "images/silence32.png",
		  "48": "images/silence64.png",
		  "128": "images/silence128.png"           
	  },
	  "default_popup": "popup.html"       
  },
  "background": {
      "scripts": ["background.js"],
      "persistent": false
  },
  "manifest_version": 2
}