### Steps to reproduce

1. Login as a project admin

2. Begin of the insertionCreate a custom field for users of type "List" which is required and has a default value

3. End of the insertion Go to the project overview of a project you own/created

Begin of the insertion4.End of the insertion Begin of the deletion 3.End of the deletion Go to any user type field

Begin of the insertion5.End of the insertion Begin of the deletion 4.End of the deletion Click on the bottom +Invite button

Begin of the insertion6.End of the insertion Begin of the deletion 5.End of the deletion Select User on the modal

Begin of the insertion7.End of the insertion Begin of the deletion 6.End of the deletion Add a name and a role and click on Next


### What is the buggy behavior?

* Modal doesn't invite the user

* It seems not functional at all

* Text field is not in the correct colour in dark mode


### What is the expected behavior?

1. Modal successfully invites user

2. Text field is in a dark colour in dark mode


### Screenshots and other files

<img class="op-uc-image op-uc-image_inline" src="/api/v3/attachments/206166/content">

### Environment information

**OpenProject version**

_dev_

**Browser**

* [ ] Chrome
* [x] Firefox
* [ ] Safari
* [ ] Mobile Safari
* [ ] Other (please specify)

**Operating System**

* [x] Windows
* [ ] Mac OS X
* [ ] Mobile iOS
* [ ] Mobile Android
* [ ] Linux (please specify distro)
* [ ] Chrome OS
* [ ] Other (please specify)