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January 2024

  • Feature: you can import a cURL command by pasting it directly in the URL field 🎉
  • Feature: introduce Clear Cache button. You can now clear the extension's background cache without having to close and reopen browser tabs. This is particulary helpful for users who intensivelly use autocompletion.
  • Bug fix: removed experimental feature that was affecting users' working with WebSockets.
  • Enhancement: removed numerical limit on delay field. We've received feedback of users who wanted to setup a delay value higher than 9999999ms hence we've removed this limit.


July 2023

  • Bug fix: JavaScript editors were missing highlighting and autocomplete due to a regression introduced in the previous release. This issue is now solved and JavaScript editors are again fully functional.
  • Enhancement: small UI improvements to bring a more consistent look and feel to the extension.


May 2023

  • Enhancement: improvement on advanced logging; log modified response payload when for modify rules that apply transformations to the response with a response hook.
  • Bug fix: address compatibility issues with fetch Response.body and Response.blob().


May 2023

  • Feature: advanced logpoints are now enabled by default when creating or importing new rules.
  • Enhancement: change delay max limit to 7 digits. We've received feedback of some users needing to apply large delays to tweak rule (sometimes minutes long!).
  • Bug fix: request autocomplete would break for POST requests with form data.


March 2023

  • Bug fix: address issue where request headers were not surfaced in request hooks in the headers object available for manipulation.
  • Enhancement: we took advantage of this iteration to also surface request headers when capturing background requests with autocomplete; only applicable for modify rules.


February 2023

  • Bug fix: in our latest released, we left request hooks out of the import/export functionality. This is now fixed, request hooks can be imported and exported together with the rest of the rule configurations.


January 2023

  • Feature: Introduced request hooks. You can now modify request parameters with JavaScript. Request hooks allow you to modify the request URL, body and headers.
  • Bug fix: address visual glitch for partial request payload matching, click was not working properly.
  • Maintenance: We've done a round of internal software upgrades to provide our users with the latest improvements and security patches.


November 2022


September 2022

  • Feature: you can now use Collections to organize your rules 🎉
  • Feature: add default logging to make mocked requests more discoverable.
  • Bug fix: address small glitch in headers table where adding a new entry would cause the main panel to scroll down.


July 2022


July 2022

  • Bug fix: address visual glitch in autocomplete functionality that causes elements to overlap.


June 2022

  • Feature: allow users to store more than 5MB of data within our extension by requesting additional storage permissions. This will now allow you to storage large payloads of data in tweak rules.
  • Feature: provide autocompletion hints for context response hook properties.
  • Maintenance: We've done a round of internal software upgrades to provide our users with the latest improvements and security patches.


June 2022


May 2022

  • Bug fix: When response payload was left empty the status code was overwritten to 0, even if users would specific a different status code. This is now fixed. Thanks for reporting issues and help keeping tweak sharp 💪
  • Maintenance: Software upgrades to provide our users with the latest improvements and security patches.


May 2022

Announcing tweak premium  ✨✨

We've been running this show for more than two years. A lot of feedback, ideas and experience are bundled into our tweak premium plan. Some highlights:

And here are a few other improvements, business as usual:

  • Bug fix: tweak was breaking websites when going into browser mobile emulator with iPhone devices. This is no longer the case tweak will work normally across normal browser view or emulators.
  • Enhancement: We did a complete revamp of our documentation for this launch, you'll be able to find accessible links to it across the extension.


March 2022

  • Bug fix: address outstanding bug affecting applications using latest axios library versions.
  • Enhancement: we ship a few security patches and software upgrades with this release.


March 2022

  • Bug fix: We've corrected some defects in our search and autocomplete functionality.
  • Bug fix: In the previous release we've introduced a not so obvious bug that was affecting some of our Firefox users. This costed us the reputation gained in the Firefox addons store for over the past 2+ years. If you've ever faced the following runtime error "TypeError: r.clone is not a function" this should be fixed in this release. 🙏


December 2021

  • Bug fix: We've improved our support for websites with iframes. This is a great deal, as it will allow you to keep using tweak even within sites such as codepen or stackblitz.
  • Bug fix: Lack of error propagation for XHR requests that are mocked with error status codes. This was mostly affecting developers using Angular and the Angular http client.
  • Bug fix: We've received reports that tweak was not working properly for applications that specifically use If you're using the the axios library. Latest axios version you might have been affected by this. This latest changes uncovered a small bug in our implementation, this is now fixed.
  • Enhancement: We now restore the previous scroll position at each one of the editors in our UI, hopefully this will save you a few seconds so you can pick it up where you left. 🏎️ 🏎️ 🏎️


November 2021

  • Feature: ✨ Smart Filters. We've enhanced the requests autocomplete behavior by allowing the combination of multiple filters, and we've introduced a new filter expression that allows you to lookup requests in the page by request payload (or request body).
  • Bug fix: We had particular bug reports where applications using the axios stopped working normally due to an update on the library. This particular update uncovered a long standing bug we had in the extension. This is now fixed, and the extension is working as per normal for applications using axios.
  • Bug fix: We had a leaky behavior, our extension was running by default on .xml documents. We've stopped injecting our extension into this document, limiting ourselves to HTML documents.
  • Enhancement: We no longer open the changelog automatically once the extension is updated. We've received some feedback that this behavior can be intrusive and we totally agree.
  • Enhancement: In this version we ship several improvements to the stability and resilience of the main components of the extension that interact with the page requests. We had several discussions with many of our users that had issues using tweak in their particular applications.


October 2021

  • Bug fix: Following the release of v4.4.0 we've received some reports of breaking behavior for a few users. A patch to that release will follow. This was caused by new features shipped in v4.4.0.


October 2021

  • Feature: New VSCode Monaco Editor integration. Prior to this integration we've used a nice editor, but somewhat heavy and limited in terms of capabilities. We hope that with an embedded VSCode you'll have a much wholesome experience. Along with this change, we've also made this editor the default for text edition (meaning non JSON data) for a better experience.
  • Feature: Move rules up/down. A new option added along side the options to delete or duplicate the item now allows you to move items to the top or the bottom the extension panel.
  • Bug fix: Fix breaking behavior in iPhone mobile emulator. Few users saw their requests blocked when opening iPhone emulators in the browser developer tools. We've added the proper safety checks in place to avoid this from happening again. We still didn't identified the root cause here, it might happened that you still experience occasional glitches.
  • Bug fix: We've received a peculiar bug report where the extension was breaking websites that would modify global objects that the extension depends upon. Once more we've added safety checks in place.
  • Enhancement: Alter requests autocomplete to scan for failed requests. In previous versions we've decided to deliberately exclude failed requests (e.g. in the 4xx or 5xx status code range). We've received feedback that these request might also be useful, so we take here a less opinionated approach and make all the requests indexed for search regardless of their status code.


July 2021

  • Feature: Added shortcuts to interact with the extension when the popup is closed. You can use Ctrl/Cmd+Shift+. to open the popup and Ctrl/Cmd+Shift+, to run/stop the extension!
  • Bug fix: For a long time now we had an inconsistent behavior when importing a .json file into tweak, and we've obtained some negative feedback on the same. From now on, the import button will open a new browser tab for you to upload your file.


June 2021

  • Feature: Dark mode 🌗   available!
  • Feature: We want to make it easy for you to report issues. We've added a new feature that allows you to download the extension error logs so that you can forward them to us.
  • Enhancements:
    • Input any status code. Can't find the status code you need? To give you more flexibility, you can now input any status code, instead of selecting it from a pre-defined list.
    • Label displayed on top of the request URL and visible also when the request is minimized. Use the label to differentiate and quickly identify your rules!
    • We have made significant performance improvements, hoping to get you a faster experience when interacting with the extension UI.


April 2021

  • Bug fix: Fix XHR mocking, missing support for load event. This fixes an issue preventing tweak from working on Angular applications.


April 2021

  • Feature: You can now expand the JSON editor to the dimensions of the extension popup.
  • Feature: Beautify JSON automatically upon request autocompletion.
  • Maintenance: Major migrations of internal software libraries we use. Please reach out to us if you detect any anomaly in the existent functionalities.


January 2021

  • Feature: Response headers - you can now specify the response headers to go along with you response mocked data.


December 2020

  • Feature: Request Autocomplete - 🥁🥁🥁🥁🥁   After some careful UX analysis we finally bring to you a autocomplete experience. You can easily set up the requests to mock without any manual entry! Simply search a request triggered in your web app and tweak will automatically import all the necessary information. Curious to know more about this one? Checkout this quick video, or our documentation to get up to speed with this new feature.
  • Feature: Wildcard for HTTP methods - You can select a wildcard option to mock/intercept requests disregarding their HTTP method.
  • Enhancement: All HTTP methods are now allowed to specify a request payload. During the initial designs we thought that the request payload would be used mostly for POST, PUT or PATCH, but it's not really our business to decide what HTTP methods to restrict. After some very thoughtful user feedback, we've remove all the restrictions on what HTTP methods can define a request payload.
  • Enhancement: Save the scroll position upon return to the extension popup
  • Enhancement: In this release we make some improvements to keep you up to date. We will notify you by popping up our changelog every time there's an update to the extension. This is the reason why we require the permission "tabs", so that we can open our page with the changelog and/or documentation.
  • Enhancement: Add copy to clipboard in the JSON editors.
  • Bug fix: Fix UI glitch in Firefox causing error messages to be hidden when using regular expressions in the URL field.
  • Maintenance: As usual we've done a round of internal software upgrades to provide our users with the latest improvements and security patches.


October 2020

  • Bug fix: Layout glitch (overlap) when toggling the JSON editor's error panel.


October 2020

With tweak 2.0, users are now able to export/import tweak rules. We hope this provides users a better way to document different scenarios and empowers them to share rules within their teams to boost productivity.

  • Feature: Export/import tweak rules. rules are exported as a .json file.
  • Enhancement: Show timestamp of last request interception in the counter tooltip.
  • Enhancement: Add a loading state to the extension popup.
  • Maintenance: 3rd party security dependencies updates.


June 2020

A bug fix and some improvements on expanding support of existent functionalities.

  • Announcement: tweak is now available on Firefox 🎉
  • Bug fix: Fix glitch in URL input field, was below the regular expressions toggle.
  • Feature: Partial support for iframes. Users are now able to intercept HTTP requests from iframes. The support we introduce is limited, the user needs to ensure he/she disables and re-enables the extension for tweak to attempt to kick into the iframes.
  • Feature: Proper support for non JSON formats. Provide different editor for users to manage non-JSON response payloads. Additionally allow users to setup mocks with invalid JSON. We believe this is a very useful feature for chaotic testing purposes.


May 2020

We're happy to announce tweak 1.0! After improving the foundations of tweak in the initial releases where we mainly focus on making sure the extension intercepts requests consistently across different websites and different environments, we decided that now is the right time to focus on new features and enhancing user experience. We scanned the extensions in the market, and we cross-referenced dozens of browser extensions and their hundreds of reviews to come up with the feature set of this version. We then re-designed from scratch the extension UI focusing on productivity and usability, and we add a few other neat functionalities to provide you with a sound experience.

  • Feature: Allow users to delay a request by a specified amount of time.
  • Feature: Add a new action on the top bar to collapse all the expanded rows in the extension.
  • Feature: Add a new action on the top bar that allows users to delete all the rules in one go.
  • Feature: Allow users to specify the request payload (request body) for POST, PUT and PATCH requests. The user can edit the request payload by clicking the Request Payload tab in the editors area.
  • Feature: Allow users to specify the Content-Type response header.
  • Feature: Allow users to specify the HTTP response status code of an intercepted request.
  • Enhancement: Overall extension re-design with major UI improvements. Some highlights:
    • Larger URL field (old URL match expression) with a new regular expression toggle and instant input validation.
    • Better interception count experience with improved active/inactive states. From this version on, the interception counter is always visible even when its value is 0. The team hopes that this serves as an indicator/call to action in cases where user is expecting an interception but does not get the expected result or neither feedback from the extension.
    • Larger and slightly more spacious JSON editor(s) with comprehensive footnote captions, to hint users towards the right direction when filling in the content based on the type of request their trying to intercept.
  • Feature: allow users to bypass requests despite the original one not being successful (e.g. status 404 or 500 are the most common use cases). Users may now simulate calls to resources that don't exist on the server, or even create their own routes in the extension to truly simulate an API.
  • Bug fix: deleting individual rules didn't stop the request from being intercepted in the background. This might cause zombie interceptions, where a request is still intercepted even tough the user deleted the rules. In prior versions of tweak the user would have to refresh the page to get rid of the zombie interception.
  • Bug fix: compute the proper header Content-Length based on the user defined payload.
  • Maintenance: 3rd party security dependencies updates.


April 2020

Although we didn't introduced new functionalities in this release, we did some foundational changes in the way that tweak interacts with your website in order to augment the coverage of scenarios where it can intercept requests. That's the reason why we also changed our user permissions from activeTab to host permissions, allowing us to fix the following fundamental issues:

  • Feature: tweak is now able to intercept requests that are fired/triggered at page load 🎉🎉🎉
  • Bug fix: tweak interceptions were flaky for applications using XMLHttpRequest methods:
  • Bug fix: Prior to this release tweak was not capable of intercepting requests to the same host when the rule had an absolute path in the URL match expression field.
  • Bug fix: Prior this release calls to window.fetch with Request object could not be intercepted.
  • Bug fix: Bubble up errors that occur during window.fetch. tweak was silencing these errors, which would make developer's job of debugging the request failure harder. In this new release, tweak properly surfaces the error to the application.


April 2020

  • Feature: By default turn on the request interception switch toggle when adding a new rule.
  • Feature: Notify users about number of intercepted requests by adding a badge counter to the extension icon.
  • Feature: Add a Run&Stop button on the top bar of the extension for faster access when in need of enabling/disabling the extension globally.
  • Feature: Small visual improvements:
  • Small tooltip for the URL match expression rule field to inform the user about advanced usage use cases with regular expressions.
  • Custom title for JSON editor present in each rule.


March 2020


February 2020

First tweak version 🎉🎉🎉

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