Suggestion: see thread in advanced mode.

I've noticed when clicking the advanced option, you can no longer see previous posts while making your post. Most forums still allow you to see previous posts when using the advanced option. This can be practical when replying to someone. I know that while I'm in the middle of a long reply, I can forget what exactly was in the previous post.

Also, while the scrolling down header is practical, when you have to add a whole bunch of new rolls on a post, it can get a bit in the way... I wonder if there is a way to reduce it a bit more when scrolling down: another 15-25% reduction probably would not hurt (your profile pic could shrink a bit too in order to help with this)...

I can look into shrinking the header more, though this was the smallest I was comfortable making it while keeping the logo readable. That said, can you clarify the concern with it getting in the way with a lot of rolls?

As for the posts in the thread, this is planned in the forum upgrade.

Well, my mounted characters are currently in a fight with 10 zombies (well, 8 left), with 2 of them being blinded thanks to a well-placed spell form one of the players, and since zombies are mindless, they have equal chance of attack the horse or its rider. So you can see that with attack rolls to make, 2 miss chances roll to make, and rolls to see whether the horse or the rider gets attacked, the "Add" button quickly scrolls up to the top of the page where it hides under the header...

Wouldn't you end up having to scroll up with or without the sticky header?

I think the problem is that when you click Advanced, it opens a new page where your current post in progress is the only one. So you can't scroll up, regardless of the header. I end up opening multiple browser tabs to work around that.