I have the same problems under Opera, which is also based on Chromium.
The problem with the notifications only shows up however if I want to check the notifications in a new tab, not the one I have open right now. No idea how that makes a difference (maybe looking for something it's expecting on the page that ain't there in a new one?), but did you try and check if there's a difference if you open up notifications in a new tab vs an existing one?
The one with the forum posts on the main page is also the same issue: pinned threads are showing up, but the rest is stuck in loading limbo. The last 2 days, it didn't show if there were any new posts - it actually looked like I was a new member with new written behind every thread and all grey, as if I hadn't read any of them yet, even if I just made the last post in that thread. Didn't mention it because I thought it was been worked upon, but looks like the porblem runs deeper than I thought.
I just tested the notifications thing and it is the same for me. Loads almost instantly in the same tab and pinwheels forever in a new tab. I guess I never open Notifications in the same tab, so I didn't realize there was a difference.
As for the forum posts on the main page, they don't load if I come to the site just by typing the URL, but if I click the logo to load the main page, they start working.