Installation error: Manifest version 2 is deprecated, and support will be removed in 2023

[ffisc]

Hi there, thanks for making this! I've tried following the instructions to install it as an extension, but got the following error:

Manifest version 2 is deprecated, and support will be removed in 2023. See https://developer.chrome.com/blog/mv2-transition/ for more details.

{
  "name": "222",
  "version": "1.0",
  "manifest_version": 2,
  "content_scripts": [
    {
      "matches": ["<all_urls>"],
      "js": ["index.js"]
    }
  ]
}