To Open the Block Filter Tab

To temporarily display the Block Filter tab, pause the pointer over the Block Filter roll-out tab.
The Block Filter tab displays along the right edge of the Dependency Viewer tab, and remains displayed as long as the pointer is over the Block Filter roll-out tab. Move the pointer away and the tab is hidden again.
To dock the Block Filter tab, pause the pointer over the Block Filter roll-out tab, and then while the tab is displayed, click the Auto Hide (push-pin) icon in the upper-right corner of the tab.
The Block Filter tab is docked along the right edge of the Dependency Viewer tab. Notice the Properties and Search tabs are also now docked, behind the Block Filter tab.