[WIP][BUGFIX] Fixed multiple select for editable drop-down

Translation for editable drop-downs:

__Tasks:__

- [x] removed selection box from edit entry
- [ ] gather feedback for my changes



__Informations:__

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| Tests pass?   | none
| Fixed tickets | none
| Doc           | none
checkboxVisible = checkboxVisible !== false;
so we can make sure, that checkboxVisible is a boolean