xenodm starts on VGA display only

Hello,

I've installed OpenBSD 6.8 on an iMac G3 (Summer 2000 edition) and there was nothing unusual during install or post-install stage, I was able to install and boot OpenBSD without an issue. 

However, when X (xenodm) starts, it ignores the built-in display. The built-in display goes dark and if a second display is plugged-in via VGA port, then that display is usable, however not the built-in display. Is this a bug or a feature? xrandr only shows 1 monitor, even when the second VGA monitor is plugged it. 

dmesg is available here: https://pastebin.com/TsEBjZNi

Can the internal display be used with X on OpenBSD?

Thank you,
Claudiu.