Custom JavaScript for Websites 3 - Chrome Web Store
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Run custom JavaScript on any website.

Overview Run custom JavaScript on any website. Added remote uploading. Run custom JavaScript on any website. Use this tool to inject custom JavaScript in any website. Your scripts are kept by the Chrome sync API and applied across domain URLs. You can inject custom JavaScript based on domain or custom Regular Expression (since v3.1.1). This extension supports dedicated tab to edit your codes since v2.5.1 You can use some built-in libraries such as * jQuery 1.12.4 * jQuery 2.2.4 * jQuery 3.2.1 * Indefinite Observable 1.0.1 * MooTools 1.6.0 or/and your own external scripts. Use cases: * Site debugging (wrong list sort, etc.) * Extract useful information from website, such as billings/orders metadata * Hide annoying popups and Ads * Custom UI * Anything you can think of :) New features: Ace Editor (formating, highlight, undo/redo by hotkeys) Draft auto save (so doesn't matter when you close the window without saving) Hosts (websites) switch (you can browse customjs of other websites) Include external script (eq. Underscore.js is cool) Thanks to: Ace - Pure -

3 out of 52 ratings

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A.May 19, 2023

This is a bit suspicious. This is called "Custom JS for Websites 3", but it's exactly the same as "Custom Javascript for Website 2", which has more than 40000 users and originally published at Also, the bugs present in v2, are still present in v3, at least in my case. Moreover in the extension description, all of the features you describe in the "New features" paragraph, were already pr... Show more

5 out of 5 found this helpful
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Jovan RalicFeb 28, 2023

Great! Just wish it had a few more features.. This is one of 3 extensions that will sink my data to the account, so that it's available on my other machine. I have installed and tested ALL CSS and JS editors. Thank you!! Please, consider adding these features: - Add a tab for CSS - Apply CSS immediately - Dark mode - Option to move the window around and resize it, like this extension does:

1 person found this review to be unhelpful


  • Version
  • Updated
    January 16, 2022
  • Size
  • Languages
    English (United States)
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