Meaning
Eyes closed and looking down, eyebrows slightly raised, mouth a small frown: a face lost in sad or regretful thoughts. It is quieter than crying, more like a sigh, and covers disappointment, remorse, loneliness or gentle sadness.
It suits low-key bad news and sincere apologies: “I can’t make it to your party after all, really sorry 😔” Many also use it for mock sorrow, like the end of a long weekend. Since it looks fairly mild, pair it with words when someone is going through something serious, so it does not seem dismissive.