Use initials for default avatar

Hello,
Something that is quite frequent in different tools, I think it could be nice for Projeqtor:
instead of the default 'avatar' that is currently used, would it be possible to use the initials of a user ? (for example, initials inside a coloured circle). (I'm thinking for example of the 'gmail' view on my phone !)

That way, for people who have not uploaded a picture, you would still be able to distinguish between different people.

Very low importance, but it could be nice