Microsoft completely abandoned IE along some older versions of MS Windows OS and support for non-WebKit Edge will expire also. Green Screen Terminal Services v4 is the last version supporting those old browsers.
There are still companies using MS Windows XP and possibility to use last Chrome version 49. Such customers will still be able to install and use Green Screen Terminal Services V4 including technical support for fixing eventual bugs. Other further development for Green Screen Terminal Services v4 is in a freeze state.
Green Screen Terminal Services v5 currently supports old browsers, however, we will gradually remove support for IE and non-WebKit Edge as Green Screens product get updates over the time.
Reason for such a decision is huge advances in web technologies in recent years for WebKit based browsers making harder and harder to support old browser versions.
Many modern features are simply not available in old browsers as WebComponents, advanced encryption APIs, other security API as biometrics, Power Management API, browser extension support and many more making only parts of our products available in old browsers.
Another reason is huge performance improvements compared to IE and non-WebKit Edge which is noticeable in daily work.