Second screen keeps losing "primary" attribute when switching to multiple display setup

I use my second screen as my primary display. However, every time when I switch from single screen to multiple screen via “extend to left”, the configuration changes to my laptop being my primary screen. I have to change it back manually every time. But I want my second screen to stay as the primary one.
There has to be a simple solution for this, does it not?

Enable this when your external display is connected and you set it up as you want.


Otherwise there is no simpler way. Your system, when there is only internal display connected will make that automatically as primary, and there will be no ghost display on sides to lose opened applications there. When you connect the external one, the system keeps the logic of primary display as the internal one.

Thanks for this suggestion but it only works the first time, for the first switch, then the “primary” property switches back to the laptop screen.