I can`t use Royal TSX to manage vCenter and ESX today via html5 interface. Safari webplugin is not supported by VMware because lack of full html5 compatibility. For example, tasks are not displayed, blue screen instead of login prompt in esxi.
Exactly, you can use a site like whatsmyuseragent.org to grab the user agent string of Safari and paste that in the "Use custom User Agent String" field in the "Advanced" settings of your web connection. That should get rid of the warning.
We are using the Web plugin to access our esx hosts. It does show a blue screen which is annoying but right click in the window and select Reload and then the login prompt should display. Irritating but at least it works. We have the URL configured for the esx host console to: https://esxhostname/ui/#/login and the engine set as Modern. I still can not get it to autofill the credentials and I have tried several different methods. If anyone knows how to get it to do that properly please comment.
We were previously able to reproduce the "stuck blue screen" issue but this seems to have been resolved in newer version of the HTML5 client.
Regarding auto fill:
There are two problems: