Other people’s work that Popchat is built with, and the licences it comes under.
Emoji
The emoji on Popchat are Twemoji. The graphics are copyright Twitter, Inc and other contributors (2014–2021) and Jason Sofonia, Justine De Caires and the Twemoji contributors (2022 onward), and are licensed under Creative Commons Attribution 4.0 International (CC-BY 4.0).
What we changed: we use part of the set, the drawings are packed into a font so they look the same on every device, and the pistol is the drawing from an earlier Twemoji release. The skin tones are the Twemoji drawings of the hands and people we offer, in their own small font.
US state flags
The flags of the 50 states and the District of Columbia are drawn from the files on Wikimedia Commons named in the notice below. Fifty of the fifty-one are marked public domain on their Commons pages. Mississippi’s current flag is not public domain: the State of Mississippi’s own statement, quoted there, is “The design is owned by the state of Mississippi and can be freely used by members of the public.” Commons files it as free use.
What we changed: each flag is shrunk and traced into a few flat colours and simple outlines, so a state seal becomes a few shapes that still read at small sizes, and the drawings are packed into a font of their own that a page fetches only when a state flag is on it. The notice lists every file, its licence and its checksum.
Twemoji · CC-BY 4.0 · The licence text · Versions and changes · State flags: Wikimedia Commons · State flags: every file, its licence and checksum