Skip to main content


Do I need to add/install something in my code?#

Absolutely not! No external application/library installation is required! tweak works as a standalone browser extension and you can work with it in any environment, from development to production. No code required!

Will this work in every web application?#

tweak has proven to be reliable, but still we acknowledge our own limitations, currently:

  • It will only apply the configurations to the browser tab where you configure the requests to intercept and activate the extension (by clicking the run button).
  • Under specific conditions combined with the asynchronous nature of the way tweak communicates with your website, things might not work at first. For that we advise a page reload after pressing the play/run button to active the extension. In some cases we've observed that this might not work at all, in that case we advise you to seek an alternative.

I clicked on the file import button but nothing happened?#

Make sure you're running tweak version 4.3.0 (or newer), we've fixed this behavior on that version.

Do I need to keep the DevTools open?#

Nope ๐Ÿ˜Ž ย . tweak will still work even if you have the browser DevTools closed! However, if you're using tweak for development we do recommend you to keep the DevTools opened, with the option "Disable cache" ticked so that you don't get tricked by the browser. For cases where you're doing a demo or doing a screen recording it's understandable that you would want to keep the DevTools closed.

When mocking a response it disappears from chrome DevTools network tab?#

Yes! But don't worry, tweak is designed to work that way. Requests are mocked at the XHR & fetch APIs level, hence it's not reflected on the network panel. Once you mock a request it won't be surfaced in the devtools. This is a side effect of our implementation decision which hopefully allows us to have more control and add more features easily as we move forward.

Is there any detailed step by step guide where I can learn how to use tweak?#

Glad you asked. We drafted a very detailed documentation page as well some awesome video content ๐ŸŽฅ.

Does tweak support window.fetch?#

Yes! tweak supports both window.fetch and XMLHttpRequest (XHR). (Spoiler Alert: it will support WebSocket too).

Does tweak work on iframes?#

We've introduced partial support in tweak version 1.1.0, it's currently something has a great coverage, therefore we acknowledge that it might not work for most the use cases. We advise to open the iframe in a separate browser tab to operate on it, if possible.

Is this extension safe? I'm concerned about my privacy.#

tweak is as safe as they come, simply because we don't store any data you input. Everything is stored in your browser. We simply collect basic google analytics metrics to track the usage of our functionalities to better serve our users. This is mentioned in the privacy policy.

I understand how this works now, can I do the same for WebSockets?#

Yes you can! And it's awesome! This functionality won't be available anytime soon. We have a closed beta going on, if you want to try this out send an email to

Why can't I add more than 12 configurations?#

Browsers limit the amount of data that extensions can store locally, this should be around 5MB (see QUOTA_BYTES for more information). For us this translates in limiting the amount of configurations you can have. But we do offer a solution for you to keep your configurations organized and have as many as you want! Checkout the import/export functionality.

Was this page helpful?