Message_Read_Receipt_Enabled Colors

Dear Community,

I really like the Message_Read_Receipt_Enabled-Feature but for me especially in the windows client the difference between a grey and a light blue check mark is nearly invisible. I would like to change the color of the unread and read check marks, but I do not see a way to do so in the layout menu.

Can someone please give me directions on how to change those?

Thanks a lot!
MSDD

anyone any idea about this?