Hyperpixel suprise

I don’t know if this is common knowledge or not but I recently acquired a hyperpixel 4.0 touch and very nice it is too.

Upon a clean install of Raspbian OS I installed the hyperpixel lovely. Them I thought I wonder what happens if I plug in the HDMI cable too a monitor too…firstly nothing but then on a reboot it worked and I had duel display hyperpixel and monitor. This also worked with the official raspberry pi display.

Secondly. I was under the impression that the picamera python library would not display live output on the hyperpixel or pi display. I tried and it worked on both devices.

Just wanted to post this as help incase anyone was searching for information.

The 4B can do dual monitors. Two HDMI or one HDMI and DSI. Didn’t know a GPIO connected monitor would factor in too though, thanks for that info.
I do believe there a dual display menu option somewhere in Raspberry PI configuration?