Lozenges are truncated after just one letter on iOS

[seanh]

I can only reproduce this on iOS (iPhone 5) Safari, not in Chrome (not even in dev tools iPhone 5 device mode):

1. Go to the /search page
2. Type in a really short lozenge, e.g. "foo" or "goo"

Problem: The lozenge is truncated after just one letter. Other lozenges that you can type will be truncated after two, three or four letters. It seems to have to do with the length of the lozenge - longer lozenges are truncated after more letters.

The lozenges in this screenshot are "f", "fo", "foo", "food", "foobar" and "diplodocus":