David Bourea

David Boureau

I create web applications

How to write a Chrome extension

06 June, 2017


The github repository is here.

It is the most minimalistic, up-to-date tutorial to build your own plugin. It works as follow :


  1. Create a directory “basic_chrome_extension” on your computer.
  2. Inside, put the 3 files “background.js”, “content.js”, and “manifest.json”.
  3. Open Chrome, and open url chrome://extensions.
  4. Check checkbox named “developer mode”.
  5. Click on button “Load unpacked extension…”.
  6. Choose the directory “basic_chrome_extension”.
  7. Good ! You should see a fresh, new, grey “B” icon next to the URL bar.
  8. Open any decent website : github.com , (or twitter.com, or whatever :).
  9. Open your chrome dev tools console : Press Ctrl+Shift+J (Windows / Linux) or Cmd+Opt+J (Mac).
  10. Click on the “B” icon
  11. Ta-da ! You should see “I’m content.js, man” in the console each time you press the magic “B” icon.

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