I think the Discourse software behind this forum is great. It does a lot of work when you visit the site to remember what you’ve read and what you’re drafting, even when you switch between devices. However this results in very slow load times each time you return to the site.
Out of curiosity, do you use an Android phone? I just tried loading on my Nexus 4 (Firefox) and I can confirm that it is pretty slow. There’s a long thread here stretching back discussing poor performance on Android especially: