What can I try if the Touch Bar stays dark after undocking?

If this happens after you close the lid with the built-in display disconnected and then unplug the external display, try opening the lid before unplugging the display cable. Give BetterDisplay a chance to reconnect the built-in screen before you undock.

This sequence avoids removing the external display while the built-in screen is both disconnected and covered by the closed lid. BetterDisplay normally skips reconnecting a built-in display while the Mac is in clamshell mode. The workaround applies to this particular sequence on a MacBook with a Touch Bar. It is not a general fix for every dark Touch Bar.

If the built-in screen remains disconnected after opening the lid, reconnect it before removing the external display. See reconnecting the built-in display for automatic-disconnection settings and reconnection methods. Changing the undocking order is a preventive workaround. It does not establish the underlying Touch Bar fault or guarantee recovery once the Touch Bar is already dark.