ThinkPad 7-Rows USB Keyboard with MacBook again
I love ThinkPad and its keyboard. Now I use the bluetooth version of the latest model, but my favorite is actually the previous 7-rows model. Feeling of key touch is excellent and traditional 7-rows key layout is a part of my sense.

However, it no longer works properly since MacBook was upgraded to HighSierra. In details, scrolling by the middle button doesn’t work and I gave up to continue to use it.
Recently, I found an update in Karabiner Elements which is a great tool for customizing keyboard layout and functionality on Mac. It now supports changing mouse motion to scroll customization. I guessed that I can use my 7-rows keyboard with MacBook again by this customization, and I found a way to make it in fact!
Firstly, we need to allow changing mouse event at Devices tab. There are two devices there. One is a keyboard and another one is a mouse. Put check the mouse device.

Next, we need to import Change mouse motion to scroll (rev 1) rule from https://pqrs.org/osx/karabiner/complex_modifications/ and enable Change button4 + mouse motion to scroll wheel (rev 1).

Lastly, maps button3 of the mouse device to button4 at Simple Modifications tab, then scrolling by the middle button will start working!

Now I can use 7-rows ThinkPad USB keyboard again with the latest version of MacOS again. If you have this keyboard in the closet due to the same problem, try this configuration on Karabiner-Elements. Your ThinkPad keyboard will revive!
