Pixl.JS 'D0' pin is false-y?

I think the subject says all.
Here is the output I got testing couple of pins:

>reset(1)
Erasing saved code.
Done!
=undefined
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|  __|_ -| . |  _| | | |   | . |
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 2v02 (c) 2018 G.Williams
>!!A0
=true
>!!A1
=true
>!!D0
=false
>!!D1
=true

// and here comes the fun part:
>!! (D0.getMode)
=true