MacOS – this button on the MacBook Pro Touch Bar

macbook promacostouch-bar

What is this button?

I've highlighted it in red in the screenshot. It seems to show up almost all the time on my Mac, regardless of what applications I have open. Pressing it does nothing apparent. If I "Customize Control Strip…" in System Preferences, it disappears. It does not appear on Apple's list of touch bar icons.

I'm running macOS 10.12.6 on a 13" MBP.

Best Answer

That looks like it is from BetterTouchTool. You can configure it in the settings for BTT:

https://github.com/fifafu/BetterTouchTool/issues/1033

fifafu: You can disable it in the Touch Bar settings in BTT (go to the Touch Bar tab, then click the "General Touch Bar settings" button.
This may require a restart of BTT to become effective.