I understood that I can add json metadata in order to set the colors using things like

“label_colors”: {
“A”: “#001F3D”,
“B”: “#002F3D”,
“C”: “#003F3D”,
“D”: “#004F3D”
},

However if I have a line chart that is composed of 2 dimensions, saying “Letters” and “Numbers” and that I can have combination likes “A,1” , “A,2”, …. how do I do if i want to color only based on letters ?

It appears that I can do it if I list everything like this :

“label_colors”: {
“A,1”: “#001F3D”,
“A,2”: “#001F3D”,
“B,1”: “#002F3D”,
…
},

However values from my second field are changing a lot and making a list of these isn’t possible.
Is there another way to do this?

Checked a lot of topics talking about label colors, tried multiple things on superset itself