Multi internal links

config.json

{
  "tabs": [
    {
      "title": "Substack Reader",
      "url": "https://reader.substack.com",
      "customJs": ["https://gist.githubusercontent.com/kofigumbs/4a9708a35807dd16f2541dc3204d6a25/raw/1579800b262aee48a3c731e0f00e3ce2d20cca01/link.js"]
    }
  ]
}

link.js

document.addEventListener("click", event => {
  for (const parent of event.composedPath())
    if (parent.tagName === "A" && parent.target === "_blank") {
      event.preventDefault();
      window.location.href = parent.href;
      return;
    }
});

I combined the two to allow drag and drop:

{
  "tabs": [
    {
      "title": "Substack Reader",
      "url": "https://reader.substack.com",
      "customJs": [
        "data:,document.addEventListener%28%22dragover%22%2C%20e%20%3D%3E%20e.preventDefault%28%29%29",
        "https://gist.githubusercontent.com/kofigumbs/4a9708a35807dd16f2541dc3204d6a25/raw/1579800b262aee48a3c731e0f00e3ce2d20cca01/link.js"
      ]
    }
  ]
}