Since today it stopped using the actual contact's first name and produces "New" instead most of the time... Probably LinkedIn changed something in the HTML template the the variable needs to be adjusted,
Kind regards
Dr Bart
Hi @Bartosz_Jaworski, welcome to the forum. 
I tried it myself now on LinkedIn and it's working fine with me, can you please send a screenshot of the context where you're using it on LinkedIn, and your snippet content (or part of it), to support@blaze.today?
I think this might only be happening on LinkedIn Login, Sign in | LinkedIn level. It indeed did work from a single profile page, i.e. https://www.linkedin.com/in/aasha-kumari-27580a174/
I've issued a support ticket as advised.
Kind regards,
Bart