Fresh installation of 18.04
Wakeup system displays the time in the center of the screen.
Click and drag to top is needed to access the desktop.
I couldn't find how to avoid clicking and dragging, I want to just have the desktop displayed after moving the mouse or clicking a keyboard key. Is that possible?
Fresh installation of 18.04
Open Ubuntu Software and install the GNOME Shell Extension called:
Disable Screen Shield
Source: Disable Screen Shield
I want to take this moment to express the need for a consistent naming system. This "Screen Shield" has been called "Drag Screen", "Unlock Screen", "lock screen curtain", "phone style Gnome swipe" and so on. It would be much easier to find a solution to a buggy application if the application had a name (that you could find).
Bonus extra, disable screen lock after suspend by installing dconf-editor and navigating to org/gnome/desktop/screensaver and turn off ubuntu-lock-on-suspend. There's no way in the regular settings.
[heavily edited, was wrong about some assumptions]
Ok so the gnome team seem to have eventually realized that the screen shield implementation of GDM 3 is an abomination. (indeed it is absolutely atrocious, without any doubt whatsoever).
And have started working on a replacement. When that is finally ready, they will be able to retire the old screen shield. And any features of it would be re-implemented (presumably from scratch, we would hope). And integrated into the new login screen itself, as a single element.
So no more separate screen shield. Getting in the way, causing a nuisance.
The place to look at this new development work, while it is ongoing, seems to be over here:
Unfortunately the new design still seems to make the screen shield a mandatory part of the login screen. This is not actually what we wanted. A good place to complain about this would be at the link above ^ (login required). Or on alan's associated blog page / article about the new login screen design / proposal.
Until / unless they change their minds, then I can only recommend people try switching over to a different wayland compatible display manager. Researching the competition other than GDM3, only SDDM currently supports wayland too. Which is the login manager for KDE Plasma. So installing this on a stock version of ubuntu could mess up your installation. Due to all it's other KDE dependencies. Therefore a fresh install of kubuntu from scratch is safer. Try out the Kubuntu Live USB / ISO Disk Image before switching.
[how i reached this conclusion]
A breadcrumbs trail of prior gnome3 bugs leading up to it. Since the gnome3 developers say they are not planning to fix the existing / current / old screen shield included in 18.04 in the meantime...
These bugs are listed in a reverse order, from new to old: