Why is my MacPro screen dim-flashing periodically, as if a snapshot were being taken?

jamesd2010 wrote:

Periodically, my MacPro (M1, Sonoma 14.5) screen dims/flashes, similar to how a screen snapshot app does. I can't find out why. I've confirmed that the "Flash the screen when an alert sound occurs" is OFF, yet it still occurs. ̶P̶e̶r̶h̶a̶p̶s̶ ̶i̶t̶ ̶i̶s̶ ̶i̶n̶n̶o̶c̶u̶o̶u̶s̶,̶ ̶b̶u̶t̶ ̶c̶o̶u̶l̶d̶ ̶i̶t̶ ̶b̶e̶ ̶a̶ ̶s̶p̶y̶w̶a̶r̶e̶ ̶o̶f̶ ̶s̶o̶m̶e̶ ̶s̶o̶r̶t̶ ̶t̶h̶a̶t̶ ̶i̶s̶ ̶t̶a̶k̶i̶n̶g̶ ̶s̶c̶r̶e̶e̶n̶ ̶s̶h̶o̶t̶s̶?̶

I've run Bitdefender scans but it is not picking anything up. Any thoughts are welcome. Thanks!

I would start by looking for an official in-app Uninstaller for your third party anti-virus.

Uninstall all third party apps that are Cleaners/Optimizers/VPN/Anti-Virus

all known to cause issues on the macOS

Third party AntiVirus is not recommended— it typically does nothing but add issues to the macOS and competes directly with Apple’s own built in security:

macOS antivirus -

Protecting against malware in macOS - Apple Support

macOS - Security - Apple macOS - Security - Apple

Apple Platform Security - Apple Apple Platform Security - Apple Support

A SafeBoot Use safe mode on your Mac - Apple Support will sort many anomalies

I also just noticed this starting to happen on my machine. I can actually force it to flash by hitting Command + S on a notepad. I'm hopeful this is just some kind of Notes update vs Malware but any further input would be welcomed.

I've checked all settings assuming it was some kind of accessibility setting, but no luck.