Information Disclosure Issue with screen unlock

[Cyborgscode]

Now that Gnome has a working screenlocker with suspend, we got an issue once the device powersup again.
As it's not the fasted chip on earth, the content of the previcouse gnome-desktop is visible for a moment.

The normal order of things to happen is: screen blank/screensafer -> lock screen -> suspend drive.

Reminds me of Fedora 18.. took gnome guys 2 years to accept, that before suspending, a screen blank (most likely the screen safer itself ) must be issued. There is nothing we can do on the LightDM Lock extension level here, at least nothing i can provide atm. I will check if i can blank the screen by i.e. putting a black picture in front, before calling dm-tool to lock the screen.

[Cyborgscode]

reported against gnome 3.38
current release: 41

needs rechecking