When the official Tree of Savior English site was launched, IMC Games decided to go with an open source forum software known as Discourse. At first, it was a jarring transition from traditional forum software such as phpBB and Invision Power Board (IPB) where everything is organized and laid out in easy-to-find sections and subsections. Discourse, instead, throws organization out the window in favor of a category system in which threads are sorted into categories and the layout of the forums changes in order of those with most recent posts and threads. So a category that you're used to seeing on the bottom of the forums can instantly jump to the top with a new post or thread made into it.
Of course, there is an option to have Discourse organize categories into a more traditional forum format, but it still feels chaotic to post on. Not to mention there's no pagination, so you're constantly scrolling down to see older threads and discussions. Heaven help you if you want to find a certain post in a thread when the thread has 100+ posts in it.
Although I've tolerated Discourse since IMC Games uses it for the English site, it certainly was the last straw for me when I tried to delete a PM I made to another user on there. The forum FAQ did nothing for me as it was composed of questions for TOS itself and not the forum software. As I had no idea what the name of the forum software was, since it was not advertised anywhere on the forums at all, I couldn't even Google an answer for this issue. I had to look through posts to find someone explaining what the name of the forum software was in order to figure out how to solve my problem. Only to find that there's absolutely no option to delete "oops" PMs. Whatever you post, whether it's a thread, reply, or a PM, it's there forever unless you can get an admin or mod to delete it for you. And in order to get that processed, you have to report it and wait. I can't imagine why you'd want to have admins and mods approve every PM deletion unless you want a wiki-like history of everything. Which, if your forums grows to hundreds of users, it becomes a very unnecessary task that would simply bloat the amount of data in the forums.
This person's blog post about Discourse's trust level system has me rather surprised at how it's so reliant on automation rather than manual approval. Perfect for lazy admins and mods, but not so for admins and mods wanting to maintain law and order on their forums. It's shown to be a very hands-off forum software that, I feel, is not good for a MMORPG forums where feedback is very important for the game's longevity.