Lock computer on ubuntu but with screen still visible

How do you make Ubuntu lock the computer but leave what's on the screen visible? I don't care if people see what's on my screen, in fact, it's my work, so I want people to see it, but I don't want them to be able to use the keyboard or mouse until I unlock it with my password.

So how do you lock Ubuntu without the black overlay?

Solution 1:

You might be able to use xtrlock.

From the man page:

xtrlock locks the X server till the user enters their password at the keyboard.

While xtrlock is running, the mouse and keyboard are grabbed and the mouse cursor becomes a padlock. Output displayed by X programs, and windows put up by new X clients, continue to be visible, and any new output is displayed normally.

Ubuntu
Debian