When closing my laptop, it turns off the internal screen, which moves all windows to the second screen. I realise that I could move all windows to a secondary workspace to not have them overlap the one on the secondary screen and I also have a feature to turn off the screen backlight on my internal monitor, but both options are not quite as convenient as just closing the lid.
Is there a way to keep the internal screen active with a closed lid?
I'm using Debian 9.5 and Cinnamon 3.2.7 on a Schenker XMG A507-vsy laptop.
The monitor uses VGA and is connected to the HDMI slot of my laptop using an adapter (no extra power needed).
This question is likely related, but the answer doesn't really explain anything and I don't want to replace the entire display manager without knowing what all the changes are.
This question is basically the opposite of my question, but unanswered.