What is the gray line on the topics page?

The dark gray, horizontal line across a forum's topic page separates "stickied" topics to all other topics. A stickied topic is one that the staff has decided to temporarily or permanently "sticky" (or "pin") to the top of a forum so that it will always be displayed on the forum's first page.

This can be done for a variety of reasons, including featuring staff content, permanently displaying a forum's positing policies, etc.

To learn more, please see our Guide to the TexAgs Forums.