There is a setting available to tentatively mitigate this issue in Chromium-based browsers (disabled by default), see Suspend network activity until all filter lists are loaded. Reliably blocking at browser launch is especially important for whoever uses default-deny mode for 3rd-party resources and/or JavaScript. tracker/advertisement payloads may find their way into already opened tabs before uBO is up and ready in Chromium-based browsers, while these are properly filtered in Firefox. This is not the case with Chromium-based browsers, i.e. Browser launchĪt browser launch, Firefox will wait for uBO to be up and ready before network requests are fired from already opened tab(s). This feature requires the webRequest.filterResponseData() API, currently only available in Firefox. HTML filtering is the ability to filter the response body of HTML documents before it is parsed by the browser.įor example, this allows the removal of specific tags in HTML documents before they are parsed and executed by the browser, something not possible in a reliable manner in other browsers. On the Web" at Asia Pacific Network Information Centre, August 2020. Source: "Characterizing CNAME Cloaking-Based Tracking The dark green/red bars are uBO before/after it gained ability to uncloak CNAMEs on Firefox. The effect of this is to make uBO on Firefox the most efficient at blocking 3rd-party trackers relative to other other browser/blocker pairs: CNAME-uncloakingĪbility to uncloak 3rd-party servers disguised as 1st-party through the use of CNAME record.
This document explains why uBO works best in Firefox. Read carefully if using uBO/webext on legacy Firefox.The removed element reappears when you reload the page.
Click Update and restart the Firefox browser.
Click on the gear icon and select “check for updates”, Firefox informs about the update via a door hanger notification and prompts for permission to install the update. Click on Firefox menu >Add-ons > ExtensionsĢ. Here is how you can update to latest UBlock Origin version in FIrefox.ġ. CNAME-uncloaked network requests will be shown as blue entries in Popup panel and logger. Now here comes UBlock Origin for Firefox to uncloak CNAME records. To circumvent this, sites are reportedly trying to load trackers via a subdomain or same domain which are called first-party trackers, thus making impossible for adblockers to identify.
Generally, the tracking scripts that served from a third-party domain (third-party trackers) are blocked by browsers such as Firefox, Safari, and brave and conventional ad blockers. Three months back a user brought an issue to UBlock Origin creator notice that a french site’s () first-party tracker hasn’t been detected by extension. While Firefox protects you from third-party tracking out of the box, if you install UBO, it will block first-party tracking scripts in the Firefox browser. The Extension brings the feature to Firefox by utilizing Mozilla’ WebExtensions DNS API, since there is no such comparable API available for Google Chrome, hence Chromium browsers may not get this feature unless such API is developed by Google.
Popular AdBlocking extension, UBlock Origin has received a new update ( v1.25) to protect Firefox users against CNAME Cloaking or First-Party tracking or DNS delegation or DNA aliasing.