Whatever gschwinds writes. I too have this keyboard, am currently writing with it and have never used the dongle. All functions work directly. Absolutely no problem.

I bought exactly this keyboard last week and am writing these lines via Bluetooth without ever having touched the "dongle". It has been proven to work perfectly. I don't know how else to connect the keyboard to an iOS device. According to Logitech, you need at least Windows 8, macOS 10.12, iOS 8.0 or Android 6.

This keyboard cannot use Bluetooth, as you are already wrongly talking about "without Bluetooth dongle". This keyboard can only be used with a Unify dongle https://de.wikipedia.org/wiki...

If your Surface has Bluetooth and you want to connect the keyboard wirelessly, you have no choice but to buy one that has Bluetooth or even both. e.g. Logitech MX Keys Plus (DE, Wireless)