This also acts as a general-purpose "deselect" shortcut since pressing
it a second time will deselect text.
This is available both in the script editor and in TextEdit fields
in use, both in the editor and projects.
The Duplicate Line script editor shortcut was moved to Ctrl + Shift + D
since it conflicts with the new shortcut (Ctrl + D). The rationale for
doing so is that Duplicate Line is a less commonly used action, and
its behavior can be replicated by copying and pasting the current line
anyway. (With no selection active, the whole line will be copied.)