Auto completion after one character appends this character after insertion

Reproduce:

QString* s;   // s is a pointer .. nevertheless I'm lazy and type '.' after s
              // instead of '->'
s.t<Cursor>   

After typing the '.' I get a listing of possible methods to choose from.
I type 't'.
This gives me a auto completion pop-up with preselected 'toStdString() const',
exactly what I want so I press <Enter>.

The result is

QString* s;
s->toStrdString()<Cursor>t   //  '.' replaced by '->' OK, but what about the 't' ?

so I get a 't' after the curser.

If I'm not so lazy and type 'to' after the point. everything is fine.

ps: Clang Code Model with exprimental Clangd activated.