The Platforms field does not accept free text

[Ainali]

Subject of the issue

In section 3. Platform Details, the field Platforms have the help text

This key specifies which platform the software runs on. It is meant to describe the platforms that users will use to access and operate the software, rather than the platform the software itself runs on. Use the predefined values if possible. If the software runs on a platform for which a predefined value is not available, a different value can be used. Values: web, windows, mac, linux, ios, android. Human readable values outside this list are allowed.

However, it is only possible to get values in the dropdown to "stick", not any human-readable values outside that list, even though they should be allowed.

Steps to reproduce

In the field Platforms, write any string and then click somewhere else.

Expected behaviour

The value should stay, and become an "item" just like when you click some of the values in the dropdown menu.

Actual behaviour

The just entered string disappears.