Wikipedia top bar right now has no indication of it being a editable textfield. The possibility of it getting confused with just a side header is higher. It is not intuitive field or inviting field for user to type into. If we improve the visual design, more users will recall to search right within Wikipedia. It will also increase overall number of searches.
Metric to measure
Number of search across mobile web
As you can see the search field (search wikipedia) is not intuitive and obvious
We want to do a small change where we improve the usability of the field by changing the visual treatment as shown below