v2: Duplicate elements easily via ctrl+D

[jdittrich]

Story: I want to duplicate elements quickly

Solution: Ctrl+D is the standard keyboard shortcut

Limitations: Does not work on mobile, we might want later to have some buttons for it.

[AlaaSarhan]

This is solved with Ctrl+D for now. Let's open one for mobile later as many other features do not yet work on mobile, like drag and drop? I can imagine another major version later for releasing a mobile friendly version