Invalid valid URL problem

[tzielenkiewicz]

Hello, I have got a strange error many times while starting WPT test on the basis of simple JS Script (involving mainly "navigate https://..."). I have also some cookies implemented. Half of times when I click "start test" with the same script I get an error "oops! URL is invalid, enter valid URL". But half of times it starts without any problem (the same script). This problem occurs when I start a test manually from WPT site and when it is started with Jenkins as well. Why does exactly the same script throws an error, and next time it does not? May it be connected to long server response time? (I don't have any other idea...)