When creating a custom master page you want to make sure to keep the s4-titlerowhidetitle class. If you don’t have this in your custom master page you can find the tag directly after the #s4-bodyContainer in your v4.master. (Please don’t edit the v4.master directly!)
<div id="s4-titlerow" class="s4-notdlg s4-titlerowhidetitle"> ... </div>
IMHO it’s a gem when editing your SharePoint page. When you edit your non-branded SharePoint page ever notice how the header area disappears, that is the .s4-titlerowhidetitle at work. I definitely want to keep this functionality in my custom master page.
For my custom master page I placed the div tag around everything in my header (logo, search, top navigation, title area, breadcrumb, and status bar container).
Now when I edit my page everything in my header is neatly tucked away, and I don’t have to scroll down to see my main content.
Thanks for reading!