Interrobang

manifest.json

{
  "update_url": "https://clients2.google.com/service/update2/crx",
  "name": "Interrobang",
  "version": "0.8",
  "manifest_version": 3,
  "description": "Shortcut: Ctrl+Shift+/ writes an interrobang character. Toolbar button displays window of characters to choose.",
  "homepage_url": "http://interrobang.dlma.com",
  "icons": {
    "16": "icon_16.png",
    "48": "icon_48.png"
  },
  "action": {
    "default_icon": "icon_16.png",
    "default_popup": "popup.html"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "inject.js"
      ]
    }
  ]
}