Unable turn off shortcut

[Admini]

Yes, that is. when I turn off it in setting page but it's seen not apply. Setting page said that shortcut disable but when I press it still active to last visited tab

It is weird.
Are you using Google Sync in cent?
If so please disable "Continue running background apps when Cent Browser is closed" in chrome://settings/system, and reset sync in https://chrome.google.com/sync, then restart the browser and try again.