Using large numbers of codon values leads to overlaps of colour highlights and crashes the text display interface
Basically, if codon probabilities are measred and assigned colours for codons which overlap by being in different reading frames but the same location (+/- 1-2 nucleotides), the GUI cannot simultaneously apply two colours of highlight to the same letters, so it gives us gobbledeygook instead.
What we need is to have a way to show highlights which stack vertically within the character height space (and do not necessarily use all of the character height) so that overlapping codon colour codes can be seen side by side.