Instructions for Saving HAR-file in Firefox

The issue: If you are faced with the problem of showing unwanted creatives, please send us saved the HAR file to determine the source of the bad impressions so we could fix the problem.

If you and/or your users can reproduce the problem in the Firefox browser, you can use the Firefox Developer Toolbar to save the HAR file, which has been available since November 2017 in Firefox Quantum (version 57).

If you have an older version of Firefox, you can download Firefox Quantum here:

  1. Press F12 (Windows), CMD + OPTION + I (Mac) to display the Developer toolbar. You also can open the Developer Toolbar from the menu: Tools> Web Development> Developer Toolbar.


  1. You will see a panel like this:


  1. Click on Network, to see request history.

  2. Enable Persist log. Refresh the page or travel on website until the issue reproduced.


The enabled Persist log will save all requests made when updating the page, including when redirecting to other pages. It’s helpful to clear the log every 3-4 updates since each page update can significantly increase the size of the HAR file.

  1. When the problem is reproduced, right-click on the lowest log entry in the Network tab and select the “Save All As HAR”.


  1. Take a screenshot of the undesired creative.

  2. Transfer the saved file and the screenshot to Clickio.