Are we looking at the same website? There's a big green button at the bottom of the page that takes you to a pricing page with three pricing tiers and the price in USD.
Oh it didn't even occur to me to click that popup since I always ignore those when I don't bother to element-block them. I found my way to the home page and clicked the premium license button at the bottom, which was the first link I was able to find about getting a paid product instead of a limited gratis one. That appears to be something different than the regular subscription though. Whose price is misleadingly quoted $19 or $29 monthly, when those are only for annual subscriptions, and if you actually want to pay monthly then it's 2x as much from what I can tell. Anyway, still annoying.
