Enter in search both ended the typing and asked the server, so the list changed just when the user meant to act on it, and opened nothing. Ask the server once typing pauses, its answer joining the list as it does, and let Enter open the selected thread, or ask at once when nothing has matched. Gmail waits a second and for three characters, and reads ten threads it lacks rather than twenty-five, as its reads cost quota; JMAP waits 0.4 s and for two.