Reply To: Flex Box working but not in IE-11 …

[Atelierbram]

Instead of editing in the vendor-prefixes ourselves, we can make the Autoprefixer plugin do the hard work for us. When you go to my fork of your demo and look behind the gear-icon of the CSS tab, you will see the option for Autoprefixer selected.

Not on Windows at the moment myself, so unsure this will solve your issue for I can’t test it right now, but I hope this helps your workflow.