macOs High Sierra keyboard shortcuts for switching windows

Hello,

I've finally upgraded to macOS High Sierra as I needed to install xcode.

However, after upgrading, I find that some of the keyboard shortcuts were changed. Especially the keyboard short cuts to switch between windows. If I open 4 windows of the same app, I was able to quickly jump to them using "Command + N" where N is one of the numbers 1,2,3,4.

However, now, it has changed to "Command + option + N". I would like it to behave like earlier. Where can I customize this? I've tried "System Preferences > Keyboard > Keyboard shortcuts" and couldn't find a way to change this.

Thank you.