Auto-Downloder Chrome Extension

September 18th, 2021
comments, tech
Let's say you want Chrome to automatically download pieces of pages, such as Facebook comments. How could you do it? I recently wanted to do this and couldn't find docs, so here's what I did.

  1. Make a folder somewhere for a browser extension.

  2. In that folder, make manifest.json with contents like:

      "name": "Downloader",
      "description": "Downloads stuff",
      "version": "1.0",
      "manifest_version": 3,
      "permissions": [
      "background": {
        "service_worker": "background.js"
      "content_scripts": [{
        "matches": [
        "js": ["content_script.js"]
  3. In content_script.js put:

    // This file extracts what you want from the page
    // and asks the background script to save it.
    // You write the code to extract what you want.
    const yourStringToSave =
        /* extension id not needed */ undefined,
  4. In background.js put:

    // This file receives messages from the content
    // script and puts them in your Dowloads folder.
    function makeDataUrl(body) {
      // We use a data: url because Chrome has
      // trouble with object URLs in Incognito.
      return "data:application/json;base64," +
      function(message) {
        const fname = message[0];
        const body = message[1];
          conflictAction: "overwrite",
          filename: fname,
          url: makeDataUrl(body),
  5. Visit chrome://extensions

  6. Enable Developer Mode

  7. Click the "Load unpacked" and select the extension directory

  8. If you need it in Incognito, click "Details" on the extension card and then enable "Allow in Incognito".

Example code: github.

(And, yes, this is how Facebook comments are back.)

Comment via: facebook, lesswrong

Recent posts on blogs I like:

A Big Problem With The Going To Bed Book

One day my dad was reading this book called the "Going to Bed Book" to my sister Nora. The book is basically about a bunch of animals who are getting ready for bed on a boat. They go down the stairs, take a bath, hang their towels on the wall, find…

via Lily Wise's Blog Posts September 18, 2023

Investing in boundaries with young kids

Putting in some work to get the behavior you want The post Investing in boundaries with young kids appeared first on Otherwise.

via Otherwise August 15, 2023

Self-driving car bets

This month I lost a bunch of bets. Back in early 2016 I bet at even odds that self-driving ride sharing would be available in 10 US cities by July 2023. Then I made similar bets a dozen times because everyone disagreed with me. The first deployment to pot…

via The sideways view July 29, 2023

more     (via openring)