VMware agrees that Flash is not the solution for the long-term. Their long-term direction is to utilize HTML5. In vSphere 6.5, they have released a supported version of an HTML5 based web client which they call “vSphere Client”. The vSphere Client is part of the vCenter Server (both appliance and Windows) and is configured to work out of the box. You can access this client by this URL – https://<FQDN-or-IP-Address-of-VC>/ui. This HTML5 based client was originally released as a fling back in March 2016 and has been releasing a new version every week.
– You can access the list of features/functionality not available in the vSphere Client released in 6.5 by the link in the vCenter Server’s landing page (https://<FQDN-or-IP-Address-of-VC>/), which links to this article
– Another source to check if a feature is available in the vSphere Client is the changelog section of the Flings page. The vSphere Client released in version 6.5 is using fling bits as of v2.7.
Updates to the supported version of the vSphere Client will probably be released on a quarterly cadence, but they will continue to release new features every week via the Fling. Note that Administrators may look to the vSphere Client Fling to get the latest features but the Fling remains UNSUPPORTED. It will take some time for the vSphere Client to achieve feature parity, but they are also continually working to make the vSphere Client a great user experience. Progress can be seen on the Fling site as it develops, and is the best measure available. They encourage you to try the Fling and give them feedback on any missing features you want to see sooner using the built-in feedback tool.