Feature Request: multiselect and freetext option together in Dropdown Editors (ComboBox)

[sir-script]

I would like to request the ability to use both multiselect and freetext option in a single dropdown editor within Tabulator, effectively creating a “ComboBox” functionality. The goal is to allow users to select multiple options from a predefined list and also add custom entries not present in the list.

Use Case:
This feature would be especially useful in cases where users need to select predefined values but may also need to specify additional, custom values.

Research:
Upon reviewing the Tabulator documentation and code, it appears that multiselect and freetext options were intentionally kept separate. However, I have not found any similar feature requests or issues related to this specific use case.
https://github.com/olifolkerd/tabulator/blob/master/src/js/modules/Edit/List.js#L187

Questions:

•	Have there been any previous technical challenges or side effects that led to separating these two features?

Alternative Solution:
As a workaround, I could write a custom editor to achieve this functionality. However, it would be much cleaner and more efficient to leverage the existing dropdown feature with a built-in option.