Where do you find "preferenes" I don't see it anywhere.
Top right corner and click on your screen name... then scroll down to preferences... or select "settings' from any thread page...... Example:
[ Latest Posts | Search | Topics | Post | Members | Self-Search | Settings | Help! ]
But if you want to set the side bar items you need to select "topics" in the upper right corner and do it from there...
Something has lately been amiss with the notification of new "posts to you." When I post, it tells me I have new posts, even though it's just the post that I just put up.
This feature was working properly just a few days ago. I don't know what's changed since then.