Macbook 16 turning off and on display rarely Working on a MacBook 16-inch for a couple of month.
Some weeks ago i started using an [Apple power extension cable](
https://www.apple.com/shop/product/MK122LL/A/power-adapter-extension-cable) - just for a couple of hours.

While working with MBP I saw a couple times it would turn the display off and on for one second or less (just like one very short blink that turns display fully off and on).

Just one, but like, once a day.

I thought it could be because of the power adapter extension.  I never used it so I returned to using the MBP's direct power adapter without the extension.

I have been working without extension for a couple of weeks and it was fine except today.  I saw one blink again, without any extension.

So I'm just curious (and a bit nervous because i can't go outside), is this some kind of static electricity that turns the display off and on for a second or is it a hardware or software problem?

It happens quite rarely but makes me write this question.
For any power related issues with a Mac I would recommend you try one time an SMC reset: https://support.apple.com/en-us/HT201295. As Apple puts it: “Resetting the system management controller (SMC) can resolve certain issues related to power, battery, and other features.”

If that procedure doesn’t fix your issue you might want to have Apple technicians run deeper tests on your hardware by booking a service appointment.