Examine source code of Quick Image Replace & Overlay

{
  "manifest_version": 3,
  "name": "Image Replace & Overlay - Quick Image",
  "description": "Rapidly overlay or replace images on any webpage",
  "version": "1.3.2",
  "icons": {
    "16": "icon/16.png",
    "32": "icon/32.png",
    "48": "icon/48.png",
    "96": "icon/96.png",
    "128": "icon/128.png"
  },
  "action": {},
  "permissions": [
    "storage",
    "activeTab",
    "clipboardRead",
    "tabs",
    "contextMenus"
  ],
  "host_permissions": [
    "<all_urls>",
    "file://*/*"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "quickimage@nikkevilu",
      "strict_min_version": "109.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "commands": {
    "cycle-image-next": {
      "suggested_key": {
        "default": "Ctrl+Shift+Period",
        "mac": "Command+Shift+Period"
      },
      "description": "Show Next Image"
    },
    "cycle-image-prev": {
      "suggested_key": {
        "default": "Ctrl+Shift+Comma",
        "mac": "Command+Shift+Comma"
      },
      "description": "Show Previous Image"
    },
    "toggle-panel": {
      "suggested_key": {
        "default": "Ctrl+Shift+Q",
        "mac": "Command+Shift+Q"
      },
      "description": "Toggle QuickImage Panel"
    },
    "activate-target-picker": {
      "suggested_key": {
        "default": "Ctrl+Shift+P",
        "mac": "Command+Shift+P"
      },
      "description": "Activate manual replace target picker"
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content-scripts/content.js",
        "content-scripts/floating-panel.js"
      ]
    },
    {
      "matches": [
        "https://*.figma.com/*",
        "https://www.figma.com/*"
      ],
      "js": [
        "content-scripts/figma-bridge.js"
      ]
    },
    {
      "matches": [
        "<all_urls>"
      ],
      "run_at": "document_start",
      "js": [
        "content-scripts/freeze-page.js"
      ],
      "world": "MAIN"
    }
  ],
  "web_accessible_resources": [
    {
      "resources": [
        "content-scripts/floating-panel.css"
      ],
      "use_dynamic_url": true,
      "matches": [
        "<all_urls>"
      ]
    }
  ]
}