Tag Auto-Complete find substrings inside tags

I hope i ve not overseen another request to this.
I am using tags to mark people like @&ForenameLastname

Now the problem is: When i type a tag with @& the auto-complete only starts with the Forename. But I also want to find the tag with auto-complete by the lastname.

So why not make auto-complete for tags searching in substrings?
So typing “@&Last” (would show @&ForenameLastname) in auto-complete.

I know this could make quick access to some simpler tags more complicated. Probably this could be configurable. Or it ist dependend wether the first letter is written in capital or not.

@&last (will not find @$ForenameLastname)

But @&Last would find.

What do you think?