When you get one autocomplete result from the quicksearch box, the return key should act like that item was clicked. Instead, it runs a normal search for your search terms. This is a bad thing, especially when the search term was a contribution ID, for example.
The quicksearch bar is useful and has WMF custom extensions, so this is worth fixing.
I tested this on 4.6 to see how it would go & I feel like the logged issue is fixed but I found that the query was returning both matching contact ID & contribution ID when I specify contact id. I think this is because 4.2 only offers to search by 'generic search string' & contribution id is added on. Ideally we would add it as another option to search by.
More of an issue - I found it was getting the wrong email address when the search returned a result for contact & one for contribution - for the second result in this case.
I think the hook for this hasn't quite ported to 4.6 correctly
OK - It looks like the 4.2 hook on quick search disables 4.6 functionality - which is confusing. In 4.6 you can search on other criteria - e.g phone - but the 4.2 hook causes it to always search on the same criteria. This warrants more work by me on the 4.6 version
@awight: As this was tagged "good first task", where exactly could a contributor find the corresponding codebase to investigate writing a patch?