Suspend Modern UI app to taskbar

Is there a way to "minimize" a Modern UI app to the traditional taskbar? I feel that having to manage two kind of taskbar, one horizontal and one vertical is too cumbersome. Is there a way to merge them into one so that I can better track the apps (both desktop and modern UI) that I have opened?

This is possible in Windows 8.1.

In the Modern UI PC settings page, go to PC and devices > Corners and edges > Show Windows Store apps on the taskbar.

This will show all Modern UI apps--now referred to as Windows Store apps--in the taskbar.

Is there a way to merge them into one so that I can better track the apps (both desktop and modern UI) that I have opened?

Pressing Alt + Tab will show a list of all of your currently running apps, regardless of whether they are Desktop apps or Modern UI apps.

As far as I know, there is not a way to pin a Metro App to the taskbar. You can pin a Desktop app to the Start Screen, but this will not show whether it is running.

If you swipe-in from the left, you will see a list of all your running apps, but "Desktop" will count as a single app, regardless of how many Desktop apps you are running. So I think Alt + Tab is the closest to what you want.

KB2919355 (aka Update 1) adds the option to show immersive applications on taskbar, which is enabled by default.