i3lock binary package in Ubuntu Bionic arm64

 i3lock is a simple screen locker like slock. After starting it, you will
 see a white screen (you can configure the color/an image). You can return
 to your screen by entering your password.
 .
 i3lock forks so you can combine it with an alias to suspend to RAM.
 .
 You can specify either a background color or a PNG image which will be
 displayed while your screen is locked.
 .
 You can specify whether i3lock should bell upon a wrong password.
 .
 i3lock uses PAM and therefore is compatible with LDAP etc.

Source package