2021 Update for Selenium Webdriver

The compatibility between Selenium WebDriver versions and Firefox versions is strict. When attempting to run a script using the latest versions of Eclipse, Selenium Server, and Firefox, only Firefox is executed and the script does not proceed. The versions used were Eclipse Luna Service Release 2 (4.4.2), Selenium JAR selenium-server-standalone-2.45.0, and Firefox 36.0.4 and Firefox 38 beta version. On the other hand, the script runs smoothly when Firefox 32.0 is used.


When attempting to run a script in WebDriver using the newest versions of
Eclipse, Selenium
Server and Firefox, only Firefox is executed, and the script fails to proceed.

  1. This is the second service release for version 4.4.2.
  2. The JAR file for Selenium is labeled as selenium-server-standalone-2.45.0.
  3. Versions of Firefox including 36.0.4 and the beta release of 38.

Scripts were able to run without any issues when I utilized Firefox version 32.0.

What technical explanation can be given for the incompatibility of the latest version of
Firefox version
with the most recent versions of Eclipse and Selenium JAR?


Kindly refer to the changelog where it appears that Mozilla has modified certain APIs that are no longer accessible, but Selenium was dependent on them.



Significant modifications have been introduced in this version.

  • Due to the lack of an API for native events in Firefox, recent versions now use synthesized events as a fallback.

In search of the latest supported version of Firefox, I discovered that several others are facing the same issue and have resorted to reverting back to v35.0.1. For more information, please refer to this link.

Frequently Asked Questions