The following review hints are still valid:
Currently, the user can enter an invalid assignee and press enter or the confirm button. The assignee is not changed, but the user does not get feedback why. We should either:
1. When the entered assignee is invalid, the conform button should be disabled and return should not apply changes OR
2. When the user tries to assign to an invalid entry, an error message is shown
If I copy an invalid username into the field using the mouse, there is no indication of invalidity.
- There are some console.info statements left in the code
- There are a lot of unnecessary requests, even if the value did not change (e.g. when using the keyboard to move the mouse cursor). There should only be requests when the value has been changed