Edge mode tells Internet Explorer to display content in the highest mode available.
This is the best setting to use.
Stephan is correct. Internet 11 is indeed supported.
What is needed to get IE supported ? Continue to get
"No constructor found for widget LoginForm.widget.LoginForm"
Internet Explorer 11 (IE11) is the last supported version of the software. There is a small exception if you're using Windows Vista with Service Pack 2 (SP2) though. On this operating system, Internet Explorer 9 is still supported
Best is to create a separate anonymous workflow for deprecated/unwanted browsers, extract the request headers for after login for anonymous, parse User-Agent using regexes from a value in a configuration, takes care of everything