Thanks for using Codebook and posting to the discussion forum. I’ll be happy to help.
The dropdown list you’re referring to are your most frequently used values for each of the fields. So for example if you have other entries which emails that have values of firstname.lastname@example.org and email@example.com those values will be suggested as soon as you start typing
s in a new Entry’s email text field.
If the emails are no longer used and you wouldn’t like them to show up under autocomplete (the dropdown that shows up when you start typing in a field) you can create a new label (like “Old Email”) and switch all the old emails over to this label. This way they won’t show up in autocomplete when you create a standard “Email”.
There’s more information here about creating custom labels: Codebook Help - Customize Labels
I’ve included some screenshots to show what I believe you’re seeing and what it would look like when switched over to the custom label.
After modifying old accounts to use “Old Email” custom label:
Let me know if I understood your query correctly and if this allows you to suppress unwanted suggestions from old accounts. Thanks!