Being able to display weight paint groups while editing bones

Sometimes, when I want to fix the position of some joints, or rather when I decide to make a model by editing the model of another character I modelled, I noticed that there is ONE function that I really miss, to know: the possibility to see the weight paint of a bone I'm editing.

It is maybe not the most useful feature to add, but for sure, it would really help me (and probably some other 3D artists using the same method) a lot.

That's why I want to suggest that as a new feature to add.