There are even photos from Mozilla's visit to Proton HQ in Geneva: https://www.instagram.com/p/BpR7ungAi6Y/
Proton does have an office in Vilnius (one of 6 offices globally), but the bulk of our staff works in our two Swiss offices.
Is Tesonet's CEO still the director of ProtonVPN UAB, more than 2 years after the incorporation in July 2016? I can no longer check it myself, because the public record is now hidden. But it was still true in June 2018.
And how do you feel about partnering on a free VPN service with a company, which has been sued for multiple patent infringements in "Large-scale web data extraction products and services with residential proxy network" by the founders of another free VPN service, HolaVPN, who have publicly admitted to using it for exactly that?