### Steps to reproduce

1. Have a user with an accent in their name, e.g. Cécile
2. Go to a work package and attempt to mention, assign, ... the user by typing in 'Ce'

### What is the buggy behavior?

* The autocompleters do not return Begin of the insertion'Cécile'
* The "Add new member" autocompleter
* The name field under "Administration > Users"
* Assignee filterEnd of the insertion Begin of the deletion 'Cécile' End of the deletion

### What is the expected behavior?

1. Autocompleters should return the user