UserAgent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/56.0.2924.87 Safari/537.36

Steps to reproduce the problem:
1. Enter to the console "onkeydown=onkeyup=function(e){console.log(e.type,e.code)}"
2. Press and Maintain "ShiftLeft"
3. Press and Maintain "ShiftRight"
4. Release "ShiftLeft"
5. Release "ShiftRight"

What is the expected behavior?
Expected console output:
keydown ShiftLeft
keydown ShiftRight
keyup ShiftLeft
keyup ShiftRight

What went wrong?
Key "ShiftLeft" does not raise a Key Up Event

Actual console output:
keydown ShiftLeft
keydown ShiftRight
keyup ShiftRight

Did this work before? N/A 

Does this work in other browsers? No
 Firefox gives same result as in Chromium.

Edge does can't be tested, no "code" attribute in Keyboard Events.

Chrome version: 56.0.2924.87  Channel: stable
OS Version: 10.0
Flash Version: 

This does work as expected with the "Control" Key.

Steps to reproduce:
1. Enter to the console "onkeydown=onkeyup=function(e){console.log(e.type,e.code)}"
2. Press and Maintain "ControlLeft"
3. Press and Maintain "ControlRight"
4. Release "ControlLeft"
5. Release "ControlRight"

Expected and Actual console output:
keydown ControlLeft
keydown ControlRight
keyup ControlLeft
keyup ControlRight