Behat
Marionette capability should be optional
The marionette capability is a Firefox-specific capability to aid in the transition from legacy versions of Firefox (47.0.1 and earlier).
It is a Boolean and this value is now checked aggressively in Selenium
4.0.0 onwards. Since null is not a Boolean, this leads to an error.
This patch removes the default value, which means that if no value is specified then it will not be included in the output, and the defaults will apply (True for Firefox; Unset for other browsers).
Without this patch you must jump through hoops to run against Selenium 4.
Fixes #376
@stof, Any chance of a review on this? This is a bit of deal breaker for anyone using Selenium 4 with Chrome, and Selenium 3 is no longer maintained (3.15 came out in August 2019).
@andrewnicols I ran into this problem too, along with a bunch of other issues. This repo seems to not be getting much attention. I recommend you switch to https://github.com/FriendsOfBehat/MinkExtension which has already fixed this problem.
