Unblock stack
Applies to: 
Visual Studio 
Visual Studio for Mac
Note
This article applies to Visual Studio 2017. If you're looking for the latest Visual Studio documentation, see Visual Studio documentation. We recommend upgrading to the latest version of Visual Studio. Download it here
If the currently selected thread element represents a blocked segment that later began to execute after it was unblocked by another thread in the current process, the call stack for the thread that did the unblocking is shown on this tab.