Message: Unable to find a matching set of capabilities error using Selenium and GeckoDriver while loading on live server

Question

I have to build an web application on a linux webserver that will use selenium with firefox . When I run the application the the linux server \"localhost:5000\" it works per

Answer 1

This error message...

Message: Unable to find a matching set of capabilities

...implies that the GeckoDriver was unable to initiate/spawn a new Browsing Context i.e. Firefox Browser session.

Your main issue is the incompatibility between the version of the binaries you are using as follows:

• Your Selenium Client version is 3.8.0 which is almost 2.5 years older.
• Your JDK version is unknown to us.
• Your GeckoDriver version is 0.18.0 which is older.
• Your Firefox version is 53 which is also pretty old.

So there is a clear mismatch between the Selenium Client v3.8.0 , GeckoDriver v0.18.0 and the Firefox Browser v53

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Solution

Ensure that:

• JDK is upgraded to current levels JDK 8u251.
• Selenium is upgraded to current levels Version 3.141.59.
• GeckoDriver is upgraded to GeckoDriver v0.26.0 level.
• Firefox is upgraded to current Firefox v72.0 levels.
• GeckoDriver is present in the desired location.
• GeckoDriver is having executable permission for non-root users.
• Clean your Project Workspace through your IDE and Rebuild your project with required dependencies only.
• If your base Web Client version is too old, then uninstall it install a recent GA and released version of Web Client.
• Take a System Reboot.
• Execute your Test as a non-root user.
• Always invoke driver.quit() within tearDown(){} method to close & destroy the WebDriver and Web Client instances gracefully.

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References

You can find a couple of relevant discussions in:

• Selenium “Unable to find a matching set of capabilities” despite driver being in /usr/local/bin
• selenium.common.exceptions.SessionNotCreatedException: Message: Unable to find a matching set of capabilities with Firefox 46 through Selenium
• Selenium WebDriver, Firefox, Centos, unable to find a matching set of capabilities
• Unable to find a matching set of capabilities with selenium 3.4.3, firefox 54.0 and gecko driver 0.17
• selenium.common.exceptions.SessionNotCreatedException: Message: Unable to find a matching set of capabilities with GeckoDriver, Selenium and Firefox