Set background color for individual lines in line number bar

I am finishing my editor navigation plugin and I have a part that temporarily marks lines. So far I am using first column of a text line to place 1 column mark which is not ideal.

It would be perfect if I could based on for instance a list of Ints set a background color of a particular line number in line number vertical bar.

There is already some ways to affect this line number bar:

  • you can set current line/other lines background color in Color settings
  • you can add breakpoint icon on top of line number

I know you can implement custom numbering scheme e.g. relative line numbers, but I didn’t see option for color anywhere.

Any way how to do this/where to start?