Adding a new output alters the truthtable

So, when the old truthtable was:

B    red  green green green
F    red  green green green

And you add in Right as an output, then the contents are NOTt shifted by one row, which means you end up with:

R  red green green green
B  red green green green
F  red red red red

The desired output is that the truth table is moved down one row, so it doesn't change:

R red red red red
B red green green green
F red green green green

The problematic there is to find out if an input has been added above and how to shift (the code uses some not very clear way of converting facings)

Start by locating the truth-table update logic and the facing-conversion code mentioned in the issue. Reproduce adding Right as an output to the shown table, then trace how rows are assigned. Done means the existing B and F rows retain their values while the new R row is inserted above them.