A recent gerrit change [1] adds a submit-form action [2] which is sent if the user hits enter in the search box or clicks the magnifying glass. I would count both click-result and submit-form actions as a success if considering search conversions.

This should be reflected in the searchdata.wmflabs.org dashboard for desktop.

[1]: https://gerrit.wikimedia.org/r/#/c/207262/
[2]: https://meta.wikimedia.org/w/index.php?title=Schema:Search&diff=12057910&oldid=11670541