Just got this feature finally working right. If you look to the right of the main forum list, you will see these little marks:

Clicking on those arrows will collapse those forums so you don't see the listings. It in effect shortens the page like this:

That same feature is on the sticky threads:

And you can close that so you don't see the sticky threads:

Anywhere you see an arrow like that means that section is collapsible.

Clicking on those arrows will collapse those forums so you don't see the listings. It in effect shortens the page like this:

That same feature is on the sticky threads:

And you can close that so you don't see the sticky threads:

Anywhere you see an arrow like that means that section is collapsible.