Running Edge in IE mode

This has been asked a couple of times, but I have yet to see a satisfactory answer. Our app opens up in the Edge browser in IE mode. You can record a test, albeit slowly. When you try to run the test, you get an unable to find object Sys.Browser("iexplore") error. Going to the object browser, you do see a Browser("iexplore") object. 

Any suggestions on how to get around this problem? We are in the process of transitioning, but it is going to take a while, so a workaround be be very helpful to us.