How to change "To" field from "Dropdown List" to "Selection Window" in Email Composer

Hello colleagues,

I'm looking for a way to customize the email composer interface. Currently, the "To" field uses a Dropdown list view (simple listbox), but I would like to change it to a Selection window instead.

Current behavior: The "To" field displays a basic dropdown list with limited search capabilities. However, when the customer has thousands of contacts, this listbox format is not user-friendly and makes it difficult to find the right recipient.

Desired behavior: I want the "To" field to open a Selection window modal, which would allow me to:

• Search freely across multiple fields
• Add custom columns to the search grid
• Have better filtering and selection options

Is there a configuration setting to change the lookup view type for this field? Can this be modified through the Section Wizard, page settings, or would it require development changes?

Any guidance on how to switch from Dropdown list to Selection window for the email composer "To" field would be greatly appreciated!

Thank you in advance.