I just installed ViperOS on my Moto G5 – and I cannot find the bottom bar with home, back and the other button. It is just not displayed. And I have not found anything on the Internet on how to solve this issue.
Problem solved. I installed a more recent version of ViperOS which does not cause any problems.
Bottom bar with Home(Circular), Back(Triangular) and Recents(Square) are called Navigation buttons. They are used to move to home page, Back from activity/opened app, and switch to currently running apps.
AOSP builds by google implements software buttons(on screen) for navigation.
Older devices contains capacitive buttons on bottom below the screen, which performs these activities. So, the custom ROM developers may skip enabling Navigation bar(software buttons) of AOSP build, which may not be required as there is hardware button present.
But, modern devices with full view display(example: 18:9), doesn't contains capacitive buttons. Software buttons(on screen) performs this task.
Motorola devices are purely stock devices which have only software buttons. so, custom ROM builds have software navigation buttons by default.
Note: Please install Official custom ROM builds.