With Hybris Sales Cloud for Customer - 1802 upgrades the silverlight is no more supported.
For administrators switching back and forth between RUI/Fiori client is a necessity.
Earlier, switching between RUI and HTML client we just had to edit the HTML URL as indicated in below blog post :
https://blogs.sap.com/2017/04/01/launch-html5-in-rui-and-missing-features/
With 1802 upgrade the url is now different than previous RUI versions. The current RUI/Fiori client URL looks something like below :
https://myXXXXXX.crm.ondemand.comhttps://myXXXXXX.crm.ondemand.com/sap/ap/ui/clogin?saml2=disabled........
To get to HTML5 Client we can add the
following parameter in the URL and voila you will be in the HTML5 client doing the Admin stuff.
https://myXXXXXX.crm.ondemand.com/sap/ap/ui/clogin?client_type=HTML&saml2=disabled.....
Hope this helps.