Using the beta version 48.0.2685.16, and there seems to be some issues with the Netflix video interface. When you hover over any element (the volume slider, episode switcher, captions switch etc.) that element remains 'stuck' on the screen and it removes the ability to use the seek bar (the red video seek bar disappears).
This behaviour has definitely only started since the upgrade to 48.0.2685.16.
I can see it happening here on Opera 49 too.
Can you check what the console says while this is happening?