I observed the usage of "Hotspot Shield" on some PCs on the network.
When checking the connection events, such traffic appears as "Hotspot Shield"in the "Web Application". Installation of the application/browser extension on that client PCs has been confirmed.
However, a traffic of "Hotspot Shield" in the "Application Protocol" and "Hotspot Shield client" in the "Client"with a blank record in the "Web Application" appears frequently on many PCs. When checking some of that PCs for application/browser extension, we found they are clean!
Cisco ASA5525-X Threat Defense High Availability
Cisco Firepower Management Center for VMWare 188.8.131.52 (build 73)
We've not contacted them yet. I've blocked all VPNs and Proxies at Firepower but Hotspot is still popping up with quite a large number of connection events.
Put it on hold for now.