Currently there doesn't seem to be API to do that but what I had done in past is to use my custom icon instead of the Box one and select it in the code. In my case it was a JavaScript code. You can use any image you want to. If you use Bootstrap icon, you can just change the color of the image, you do not need to have seperate images with differnt color. Hope this helps.

Bibek, could you share step by step instrcutions of how to do this?