Xwayland doesn't get input in some special way, it uses the exact same Wayland protocols to get input events as native Wayland apps. All claims about it being more complete or anything like that are nonsense.
Krita forces Xwayland because they have some X11 specific code they haven't bothered porting away from, that's all.
KDE did bother, this does neither happen with KScreenlocker, nor do non-screenlocker windows show in another way, because the screen locker is integrated with the compositor.
If the compositor crashes or gets disabled somehow ofc though, that integration doesn't help either and you have to rely on a mountain of bad hacks as well as the hope that the screen locker doesn't also crash for nothing to happen in that case, but it's as close to secure screen locking as you get on Xorg... in the end the solution for secure screen locking is still Wayland.
S3 is standby. Hibernate is S4
It's been possible for a long time, but yes, now you can do it intuitively in the shortcuts GUI
You'll need to specify what DE you're using. This comes built in with KDE Plasma: Meta+left and then quickly also up for top left corner, Meta+right and then quickly also down for bottom right corner etc.
I don't knowt what exact shortcuts other DEs use, but I think most that aren't Gnome support quarter tiling too
I'd recommend you to make backups either way. I've had a SSD with SMART status "good" very suddenly die before, so don't take any chances!
All it ever was intended for was to make us feel like something was being done while doing absolutely nothing.
It certainly does help a little bit. But it's of course still not a coincidence that companies are pushing for it instead of more effective measures... It's not just cheap but it also pushes people to believe that measures to save the environment are all useless and annoying, and makes them less likely to want more to happen.
The very next words are "but it was my responsibility"... what exactly is bad about that statement if you don't intentionally cherry pick a bad quote?
Why would they do that? They're intentionally not supporting OpenGL, so that people use their proprietary API
Telemetry wasn't a factor iirc. The biggest reasons for this change were that
... or targeting Microsoft again too
This is about dragging a tab out of or into a browser window, and letting the compositor know about it, so it can move and place the window accordingly. Apps don't get to place windows themselves.