obviously it's referencing the left-pad incident[0], and to 'justify' text is another kind of text manipulation[1]; but with the more common definition, i guess it's a joke about justifying something? The Left? idk
[0] https://en.wikipedia.org/wiki/Npm_left-pad_incident
[1] https://en.wikipedia.org/wiki/Typographic_alignment#Flush_le...