Tried watching the Europa League games on the sport.bt.com tonight - was able to access via the Edge , Firefox and Chrome .
The one issue I detected was that switching to full screen viewing of the game it did so correctly on Edge and Firefox but not when using the Chrome browser - instead the full screen mode looked like it zoomed the image rather than displaying a correct full screen image.
The Pc is running Windows 10 and Chrome Version 45.0.2454.93 m