Steps to reproduce:

1. Open your wiki and go to alpha
2. Open the search bar by pressing the search icon
3. Type something ind and submit the form
4. On the search result page click the search icon

Expected: like in stable and beta, you can edit your query
Observed: the input is empty

Suggestion: It's not clear, that you can edit the query when you click the search icon, so i suggest to:
a) hide the search icon and enable all fields of Special:Search (e.g. the input field) in alpha
b) use the stable/alpha search bar in alpha always when on Special:Search