'Not a PNG' error on latest Grid using firefox

[mpanin]

Selenium Grid version 3.0.0 is being used.

Output of gemini --version:

3.10.8

Contents of .gemini.yml file: rootUrl: http://our_site.html compositeImage: true screenshotsDir: 'screens/desktop' windowSize: '1280x1024' httpTimeout: 120000 sessionRequestTimeout: 180000 retry: 5 sessionsPerBrowser: 3 desiredCapabilities: screenResolution: '1280x1024'

system: debug: false

browsers: firefox-latest: gridUrl: http://our_hub_location/wd/hub desiredCapabilities: browserName: 'firefox'

Result:

On grid machine I'm able to see that instance of Firefox is created, however it's not going any further.

Console output: Cannot launch browser firefox-latest:
Not a PNG

Expected behaviour:

Firefox was able to navigate to the page and make a screenshot

[LarsHassler]

I've got the same Problem with Firefox (Version 49 & 48) running on Browserstack. With 47 everything worked fine.

As I see it the base64 encoded screenshot coming from firefox is an empty string.

[sipayRT]

its problem with new Firefox version - API was changed for it. And new API does not supported in wd yet

[jenkinsw1]

In case anyone else has a problem with this even when using an old version of Firefox I had to revert to the older version of selenium-server-standalone for my hub & node, dropping from 3.0.1 to 2.53.1. Then my tests would run against FF47.0.2.