They have a paid hosting offer, but you can also self-host it for free. And it’s open source.
Yeowch. $50/mo is a huge cost for anything that's not making money.
Also anything that’s $50 a month doesn’t compete at the low end (which is where most OSS discussion hosting would exist) with Discord, which is free.
MacBook M3 Pro with Firefox.
And to test many replies you actually have to see them since they're not loaded on page load, only when you get to the bottom of that page, so just opening the top doesn't test anything re. lots of replies
You can host it yourself for much less than $50/mo, some people run small instances on a raspberry pi (I work for Discourse)
Pagination works fine tho, for their demo page at least. An example long thread, [1] has a clickable link to [1]?page=2 at the bottom of the page.
But you can't post. If you log in (using javascript) it refuses to show you anything without javascript later, and you can't post a new message.
It's clearly not their priority, and I am not sure why.
[1] https://try.discourse.org/t/is-the-second-amendment-still-re...
[0]: https://flarum.org/