An eye inside a speech bubble. It came from an anti-bullying campaign, where it meant "I am a witness": someone who sees bullying and speaks up.
Few people know that origin today. Most use ๐๏ธโ๐จ๏ธ for a mysterious or eerie feeling, "I see you," surveillance, or someone who notices everything. It fits cryptic posts and spooky aesthetics.
It joins ๐๏ธ and ๐จ๏ธ in one sequence, so a device that does not support it shows the two separately.
Facts
Eye in speech bubble ๐๏ธโ๐จ๏ธ is an emoji in the smileys and emotion category, under emotion. It became part of the emoji standard in Emoji 2.0, released in 2015. It is a sequence that joins ๐๏ธ eye and ๐จ๏ธ left speech bubble. Devices that do not know the sequence show those emoji side by side. On GitHub, Slack and other apps you can type it as :eye_speech_bubble: or :eye_in_speech_bubble:. People also look for it with words like โballoonโ, โbubbleโ, โeyeโ, or โspeechโ.