HyperSwitch alt+tab broken?
After months of digging I found out what was my problem. As I visited this page like a million times I'll leave here my story as it may be helpful

My issue was related to the new "Secure Input" feature of os x. When Secure Input is enabled, apps like HyperSwitch, Contexts etc... will not be able to grap hotkeys.

Some app may be bugged and not release the secure input lock, or (like in my case) you may have some issue with Iterm2. In this case just disable it, Iterm2 menu -> Secure Keyboard Entry and you have your life back!