Continuing the discussion from Claim Your Welcome Gift at the New Empires & Puzzles Store! :
This info is misleading, as “default browser” means something different than “system built-in browser”.
“default browser” is the browser the device is told to use, when you open a webpage from any other aplication - and it can be any browser user installs from the shop.
And in this case, to connect to the game you need to use your system built-in browser, even if you changed the default browser to one you installed from the shop.