Marking mesages that arrive to various labels (according to mail tules)

The Problem

A lot of times I see a red color on the mailspring icon in the system tray. It means new mail arrived.
However, I have many labels (folders) and rules that moves messages to those labels.
That means that I do not know where are these messages.

Proposed Solution

I suggest to use a unique color fot the labels that automatically received those messages. That color should be valid until I open the label.