Examine source code of GitLab: Sharp avatars

{
  "author": "Tim Babych",
  "browser_specific_settings": {
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  },
  "description": "High-resolution project and user icons in GitLab",
  "homepage_url": "https://github.com/tymofij/gitlab-retina",
  "manifest_version": 2,
  "name": "GitLab: Sharp avatars",
  "version": "1.0.4",
  "icons": {
    "128": "diamond.svg"
  },
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        "https://gitlab.zgtools.net/*",
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        "https://salsa.debian.org/*",
        "https://source.ind.ie/*",
        "https://source.joinmastodon.org/*"
      ],
      "js": [
        "gitlab-retina.js"
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}