This note has been merged into a single, updated article.
After upgrading to vCenter Server 8.0.3.00200 (8.0 Update 3b), the vSphere Client could become unresponsive after a long idle period. The cause was a changed Tomcat default (RECYCLE_FACADES), described in Broadcom KB 377734. It is fixed in vCenter 8.0 Update 3c and later.
The full article covers the symptoms, the KB workaround, the fixed builds and how to set the vSphere Client session timeout in vCenter 8.0 and 9.x:
